From what I could tell, the Disney-MGM park as a whole regularly has more and more varied (as in locale) vistors than does California Adventure. I've never been to either park, but if I had to choose, I would pick Disney-MGM, since it was developed well before the Great Decline of Disney (i.e. 1995-present). From accounts on SaveDisney.com, California Adventure was developed on the cheap and contains much fewer attraction than next-door Disneyland (which I have been to and enjoyed). Yet, admission to California Adventure costs the same as admission to Disneyland. All in all, I would not be surprised at all if Disney were to close down California Adventure if and when Eisner is removed from power.
ObGameShows: Celador is suing Disney over licensing rights of WWTBAM (Woolery left Wheel territory, I know:) )