Guarantees are few and far between, but here's some things that give me hope for the project.
1) While it may or may not be the right path to take - monthly fees are actually a good sign for the project. This indicates to me that it's an ongoing effort, and something that, because it generates its own revenue, should also get its own dedicated resources so it can continue to evolve.
2) Competition in the marketplace. When the 2# character generators happened, there was little (if any) competition for the idea. With 3E there were other options, thanks to the OGL. At DDXP I talked a little with the guy that maintains HeroForge, and he was talking with WotC about how to adapt his project to 4E.
Between that and the project from CMP, there's competition in the 4E space. If WotC doesn't keep evolving their product and truly try to make it THE best product, people will go to the competition.
And since the others have one-time fees, WotC has a bigger stake in making sure they succeed (to keep getting that monthly residual).
3) The modularity of the new rules seems like it will lend itself well to being applied to a new character tracker and all the other tools as well.
Mind you, these are all just opinions, but short of any LITERAL guarantees from WotC, I doubt you'll find much else.