I'm recently found out that California treats capital gains as normal income. No fun.
Most states tax capital gains at the same rate as ordinary income.
And then 10 states don't tax income at all.
The part where CA chases your stock grants/options for years after you leave the state is a bit less reasonable to me. (But I'd guess some other states do the same)
(Everyone, including the IRS, treats short term gains as regular income.)