For me the bloatware was Firefox 3.0 that installed itself against my wishes.
I was using then Firefox 2 or 2.5 (don't remember) quite happily.
It was just great (compared to Explorer).
Chrome showed up... But Firefox 2.5 was still much better.
Then one day, Firefox started to INSIST to install 3.0, then 3.5, then one day it just did, no matter how hard I tried to keep my old version.
And then behold, Firefox 3.5 had a bigger interface, that used more screen space (and I am in Brazil, bigger screens and bigger resolutions get expensive FAST, my current laptop, that is a ASUS gaming one, is still 14 inches and the maximum vertical res is 768, screens better than that were unaffordable to me), and it was SLOW, VERY, VERY slow, like RIDICULOUS slow.
So I hopped into Chrome... and I wish I could say I never looked back, but hogging 600mb just to load reuters.com webpage is NOT nice.
I am only still using chrome for google-ecosystem reasons.
If I could get rid of relying on google stuff (several work-related things depend on google) I probably would get on Firefox or Opera (or see if I can put Konqueror on Windows? I never tried that...)