When I got the Froyo update on my Evo I immediately noticed two major changes; the phone became VERY snappy (opening apps, swtching screens, scrolling), and the browser really came to life - page rendering after Froyo is significantly faster on 3G (I don't have 4G here yet) and ever faster on wifi. I can only imagine how much better this phone will get with Froyo, the Epic is already snappy and the browser on wifi is faster than my Evo's.
The other two features that I really like about Froyo are Voice Actions (really cool and useful), and how you can do multiple updates to your apps from the market by just pressing one button. Chrome extensions can be cool to have but I haven't use this enough to say is useful. I haven't moved any apps to the SD card as I still have good internal storage space (don't have that many installed), but is nice to have this option if needed.
Froyo broke a couple of my widgets but those got updated really fast, none of my other apps were affected and by now most major apps have made the upgrades for Froyo.
2) Real Flash to view web content. ( Hulu ....will it be possible..)
almost a definite no to hulu. hulu has been blocking access to just about all non computer devices for years (other than w/ hulu plus on ios now). when new devices show up w/ flash, it typically works or there are simple workarounds to get it to work (ps3, evo w/ flash, etc), but it gets shut down quickly.
Also, the Galaxy Tab is on its way. Given that it's running 2.2 and has similar specs to the Epic, I can't imagine it being too difficult to bring over. As far as I can tell, we are looking at a different camera and a 4G radio. Worst case scenario, hackers will bring it for us.