Expansion of the Pokemon Global Link.
I only got back into Pokemon with B/W, so far the online side seems to be an interesting idea, part mini game collection (Dream World), part social device and apparently something of an online track with Global Battle union (no idea, have not used that section of the site).
The only problem is that they should give more control over Dream World, so the pokemon you encounter aren't just random but could be at least of the particular type or game so people have a shot at catching one that isn't available to them. Don't care much about the social network aspect of it, since it appears aimed at kids but the Global Battle Union could be improved for a more streamlined approach with a few more incentives for participating.
But as franchise, short of getting the Global Link or another highly popular spin off from the main series of games, I can't think that Pokemon can get any bigger then it is.
