I installed 3.0.4 two days ago, and my TP is a bit snappier for sure. I hadn't done any overclocking or anything previously, so for me it was worth it.
My 2 main beefs with webOS still haven't been addressed though. I find typing stuff really laborious as the on screen keyboard doesn't seem to have any sort of error correction. For example, I type 'a' and as my finger is coming up it brushes the 's'. I would expect the TP would ignore the 's' and register 'a', but no, it registers as 's'. As a result I constantly have to keep going back to correct stuff, which leads to my second complaint - no back arrow, and it's nigh on impossible to click to the exact letter you need to edit unless you zoom in a lot.
The funny thing too is I thought it would be easy typing on TP because the keyboard is nice and big, but in actuality when I use the tiny keyboard on my iPod Touch I make much fewer mistakes. Also, the iPod has this really cool feature where if you hold your finger down on text you've written it will enlarge just that area, and then you can drag the cursor to the letter you need.
These are little things, but it does make a big difference in the user experience.