Long story short:
WotC underestimated how much work it would take to put out the Game Table and the rest of the DDI tools and didn't meet the original announced date.
Since then, they ahve focussed work on one tool at a time. They have put out a character builder, a monster builder and are now at work onthe next tool, which we don't know what it is. They tend to not give release dates until something actually is ready for release.
In theory, they are working on an un-named supa-secret tool. But I would hasten to add that the previous is the theory of us players. Not from WotC. So far as they have noted, they may well be all done with the tools they intend to put out and are engaged simply in maintaining CB, Compendium etc.
I am sure that it is possible when I talk to WotC_Trevor (who is the Community Manager) and ask him about stuff like this that he is lying to me when he says "we are working on the next tool, but I can't tell you when it will be announced".
But I doubt it.
I promise to buy tons of tileset and monster pack addons.
I don't care about the most recent Dungeons magazine additions to existing tools. I don't have time to read Dungeon Magazine or play those games.
I mean how large percentage of the customer base actually has time to play those adventures and need the additions in Monster/Character builder?
Drop that pleease.
I understand that new books sell well to existing customers. Some of them. But you will reach a whole lot of new customers instead with a fancy (even basic) 3d gaming table and attract people like me who like computer aided playing.
I understand the complications and costs but it should be doable. Just don't try to keep up with the ever expanding rulesets for gods sake - you'll need to make basic money first.
C# dotnet is a lovely choice.
Actually, the percentage of players who benefit from the tools already present is pretty damned large. Dropping it would be a horrible, horrible mistake - one that might tank all efforts altogether.
I'll contradict myself heavily and state that I don't need the umpteenth version of a binding spell or a goblin in the existing tools because I can build them myself.
But I would like to see them added to the game table over time.
Then again, I realize people like me can use MapTool, Battlegrounds or Fantasy Grounds for this. I will start using MapTool I think, but I would rather use an official tool of course. MapTool seems good though so I'll get by.
My gut feeling is that the developers are using all their resources on maintaining existing (basic and low value) tools instead of creating high level valuable tools instead.