Now that this year's E3Expo is over, I thought I would summarize the status of the various upcoming Mega Man titles.
Mega Man Battle Network 4 and Mega Man X: Command Mission are still on the way for a North American release later this year. You can see the expected release dates on the right column.
Unsurprisingly, Mega Man Battle Network 5 was confirmed by Capcom to be in the works. There are no known details besides the fact that the game is coming. In other Battle Network news, a game was announced for the upcoming Nintendo DS system. It's not known yet if that will be MMBN5 or a completely new game. I'll add those two to the release dates section when more information is available.
The various versions of the Mega Man Anniversary Collection are on their way as well. It was confirmed that the Mega Man 1 to 6 games included in the GameCube and Playstation 2 releases are the Complete Works versions that only came out in Japan a few years ago. The GameBoy Advance version, which was previously known as Mega Man Mania, will have the five original Mega Man games for the GameBoy with added color. While the set has the same name as the console versions, the content is completely different.