Disney is purchasing Marvel for $4 billion. Disney is obviously larger and has more money, which could be good, but it’s not like Marvel really needed bigger budgets. Both Joystiq and the OC Register wondered about Disneyland rides featuring Marvel properties. I doubt these possible new rides would even be that out of place. The Pixar characters already have a vastly different feel than the classic Disney movie characters or the Disney characters such as Mickey and Donald, my favorites.
Disney already owns a few movie studios whose movies definitely aren’t all aimed at children. However, Marvel could easily be refocused at children. Children already love many Marvel franchises despite the containment of mature themes. I wouldn’t want Disney to focus Marvel exclusively on a younger audience, but I don’t think they will. Maybe we’ll see Spider-Man dancing on a float, and maybe we’ll see some more Marvel cartoons on ABC or Disney Channel.

 
Both Disney and Marvel also suffer from a similar history in gaming. Occasionally they’ll release a good game, but most of their games aren’t worth playing. Disney hit their peak on the NES, and Marvel… well, Marvel made Maximum Carnage on the SNES, which was awesome, and Marvel Ultimate Alliance was mildly fun. I guess this can’t hurt Marvel games! Maybe we’ll even see a game featuring characters from both Disney and Marvel, although I’d prefer an action game to an RPG like Kingdom Hearts. We’ll see.
On a side note, the OC Register’s entry in their RSS feed about this was titled “Disney buys Marvel and Spider-Man for $4 billion.” Marvel and Spider-Man? What a stupid thing to say.
Sources: Joystiq, OC Register