Here's how I moved...
Treo 300 --> Treo 600 --> Treo 755p --> Centro --> Pixi --> Pre -->
(GAMEBREAKER) Replenish
POSITIVE THOUGHTS -- I like it. The keyboard is kinda cramped, but it's good with its extra keys (arrows, voice search buttons, etc.). I'd rather a cramped keyboard with more keys than I need than not enough keys, like the Pixi/Pre. There's an additional voice dialer button, as well as a dedicated camera button. VERY NICE!
Battery life seemed fairly bad for the first couple days, but I did a full charge & discharge times 3, and am now keeping it topped off as much as possible. Today, I got at least 10 hours off the charger, and the phone is telling me it's at 78% battery life now!! I even installed several apps from the Market and made a few phone calls. The Pre seemed to be able to drain at close to the same rate, but that wouldn't include installing apps. Installing apps on webOS would bring everything to a hault and cause MAJOR drain. Also, I bought the solar panel back but haven't gotten around to using it yet since I was breaking in the battery. That should be fun while I'm riding my bicycle, tho.
Umm.... Other obvious positives?? I'd say the "Voice Search" app is just mind blowingly awesome. I am keeping this phone because of Voice Search and Google Nav (had no clue it was included on the Replenish until after it shipped). Google Maps is also quite pleasing to look at on Android, as opposed to webOS.
Another positive? This phone has a compass, which is something that most other sites said it DIDN'T have. It has an all-in-one magnetometer & accelerometer. I was trying out Sky Map and was freaking shocked when the stars were actually lined up in the proper direction... and they STAYED that way when I moved the phone around my body. Mind blown again.
All my contacts were stored in my Google Account, so signing in got them all transferred over, just like would have happened with Synergy.
I can "Just Search" anywhere on the home screen and in just about every app, just like one could do with webOS 2.0's "Just Type". This searching on Android is so much faster, however.
What else? The Power Control widget for Android is the equivalent of webOS's patch -- "Device Menu Megamix", tho not
quite as powerful (i.e. - no flashlight & phone radio toggles), but still plenty powerful for me.
One thing I really liked is that the stock browser uses the spacebar as a page down button (no patch necessary like webOS) and shift+space as page up (not as friendly as just pressing period key for one handed action, but still.... at least Samsung doesn't have their head completely up their ass). Sucky thing about the stock browser is NO MULTIPLE browsers/tabs. Miren Browser has tabs, but then I lose my page down functionality.
Speaker volume is good. Call quality is good.
NEUTRAL THOUGHTS -- My thoughts on Android multitasking are neutral. It's not as good as webOS, but it does work. Leaving apps open that I don't want open just drains the battery. They have task managers/killers, but forcing them could cause corrupted files later down the line.
The Android Market is a neutral thought for me, as it stands. I seem to never really find "the goods". Sometimes, the same app seems to be listed 3 or 4 times. 100,000 apps divided by 4 = NOT 100,000 apps. A lot of the apps seem to be absolute garbage. You must ask around to find out what apps are worth a dern, and I haven't done an incredible amount of asking yet.
The notifications aren't as bad as I originally thought, but sometimes things are hidden from me. That seems kinda hard to believe because there are multi-colored led indicators, tho I haven't quite figured out how/when they blink.
The menu button is one of the hardest things to get used to in Android for me (instead of swiping down from top-left of screen w/ webOS). I just forget to do this in some Android apps, and it looks like they suck so bad. Then I close the app and realize later I forgot to open the menu, then they don't suck as bad, but still suck.
How about the camera? I'd say it's a neutral. I was expecting TERRIBLE results after what I saw in the store, but it's at least better than a Treo 650.

Nothing like my Pre's camera, but it will certainly work. I think I had to adjust the brightness a little lighter before I could tell it wasn't AS BAD as initially thought.
NEGATIVE THOUGHTS -- There's only two things I can think of that I dislike about the phone, and one of them you can resolve before it's ever really a problem for you.
(1) Screen -- The resolution is fairly bad, but the phone cost me ZERO of your favorite currency. I can deal with it to get the hardware keyboard. Must have keyboard!! After a while, you realize that the screen is just there to work (like all the other components), and it does its job just fine. The crappy part is that the screen is plastic. Didn't really pay attention until I went to a sandy area and had a few scratches before it even touched the sand... perhaps even just from my thumbtip or pulling it out of my pocket. Ordered a PhantomSkinz with "summersale25" coupon, so won't be a problem for much longer.
(2) Internal RAM -- This is really the only negative about the phone that is going to piss me off. It actually comes with a 2GB microSD card already in the phone (had no idea), but only a couple hundred MB or so of internal storage. This is the only real limit of the phone. they gave it plenty of RAM, but not enough internal storage. Most apps can use APP 2 SD, but not all of them. I've only got 28 MB free of internal storage now!!!!! I'll be able to
remove some of the junky apps, tho. Had they simply given a whole GB of user-available internal storage, however, I would have paid an extra $50 easily and recommended this phone to everybody and their brother. But it's hard to do that when most people want a big qHD display and apps, apps, apps. I'll let them choose what they want instead of attempting to influence them, whereas I would've gone overboard with word of mouth had it simply had 4 or 5 times as much as it has now.
ALL IN ALL -- I am very happy with this phone. Very happy. I prefer plastic screens because they're not going to break, and that's a good thing since I don't have insurance. Just wish I'd known that beforehand so I would've ordered the PhantomSkinz screen protectors. But besides that and the internal memory "limit", which likely won't bother me until next summer... this phone has given me far more than I was expecting. Voice Search, Google Nav, and compass for functional Sky Map and other compass apps. Don't expect the greatest things from the non-Google apps, which is 99.99% of what's in the App Market, but there are a few gems here and there. The good thing, even tho the Market is cluttered beyond belief, is that there *is* a solution in there.... somewhere!! You've just gotta find it, and that's why the internal storage limit likely won't be a problem 'til next summer.
And SHH!!! Don't tell anybody I'm here. :-X