I'm stock, and I see no reason to root for my uses. I am a PC junkie, and have hacked pretty much every console I've ever owned, so it's suprising that I am staying stock on my Bionic. To me it's just not worth it when all I gain is the ability to tether (which I would never use), and Titanium Backup (I back up all my APK on my PC). But I fear that I could mess up my upgrade path, and yeah there are probably ways to fix that, but I really don't want to take the time to try to troubleshoot it. Also I don't want to have to deal with removing root and such if I ever have problems with it. And the "Bloatware" really isn't bloated on here. I have my phone loaded to the gills and still is blazing fast.
Honestly to me, the risk just isnt worth the gains for me. If there were more things rooting could do that were appealing to me, I'd probably do it, but for now I'm loving my Bionic stock.