i hate it. the new leveling and stuff is sped and potions and enchanting is just, no. and i was playing around with a new mod and it wasent compatible with ic2 i guess, and i didnt have a back up. so now im stuck in 1.0.0 till ic2,BC,and RP updates. FANTASTIC -_-
That's why one keeps seperate folders for their modded and vanilla minecraft installs.
I use this batch file for my current 1.8 modded install:
Incidentally it also makes the install 100% portable, I can just dump the folder on the flash drive and copy it to the laptop later for play there.