It seems very plausible... Perhaps they will make some sets of the previous movies aswell, just like with Indiana Jones.
And of course if that happens, we will see LEGO Jurassic Parc: The video game...
It sounds a bit like they are milking Spielberg/Lucas movies when I say it like this, but they would be stupid not to make a game.
All these movies translate very well into lego games, imagine:
The main base (just like the bar/cantina in Lego Star Wars) would be the park research centre, where you can "cook" up your own minifigs in the kitchen.
The three movies (IV will most likely be a seperate game, 6 months later you can buy the together with EXTRA content!) will be devided in funny little chapters.
Also, the movies have scenes very fit for Lego parodies, the cow beeing fed to the raptors, we all know what that will look like...