Well last year, 2 highly anticipated games were released, Super Smash Bros and Grand Theft Auto 4, which boosted the sales of the consoles they were released on, but this year, the big titles for each console, Killzone, RE5, Halo Wars, and others, have already been released so in comparison, these months with nothing MAJOR coming out will seem sub par and to analysts may seem like a slow down of game sales. In the end though, I believe that game sales will rise again as more people anticipate bigger named titles later this year.
With Lego Rock Band, they have gone to far, but in terms of Lego Universe, they are on the right path with the open ended world of an MMO that is based on Legos, that is a stellar idea but other than that, they have no need to make any IPs into a Lego form.
At the moment, they have no need with the projected sales of the DSi within the first two weeks to be above 435,000. But in terms of appealing to the "core gamer" then they need to as soon as possible because there isnt a very "core" game out on the handheld yet. With LOZ: Spirit Tracks coming out this winter, where are the First Party DS games, other than Starfy? They also need to release at least one good DSiWare to get people to realize the awesomeness of the downloadable games.