this is great so far. i actually uninstalled launcher pro. the improved blur is really nice and smooth. no more wading through all your facebook contacts to find a number. just untick a box in the contacts menu and they're gone. the only problems i've run into are from not wiping prior to installing GB. for example, i froze my blur email program on apex, and now i can't check my hotmail on my phone. not a huge deal since everything important goes to gmail, but i'll probably wipe and resinstall stuff once root is gained and i can restore app data.
for anyone scared to take the plunge, i would say if you are comfortable enough to sbf, there is no reason you shouldn't just at least try it, just backup before. when you are ready to go back, flash the .340 sbf, reroot, and restore your backup (but you knew that already)