And... did you notice that you'll be paying for the service before all the features are ready? I really, truely hate being a naysayer here - but the fact that you are going to be paying for the things are are available now, while the character creator is still being developed, is a total pile of crap.
"...So September is the last full month of the free trial and this month’s compilations will be the last full free issues of Dragon and Dungeon Magazines that we make available. We probably will not be done testing our Ecommerce and Entitlements system in time to launch by October 1st, so you’ll probably get a couple of extra articles for free as we continue to publish three times per week..."
In case you missed that last point: I CALL BULLSHIT! VAPORWARE!
Are they kidding? The best part is that all the other tools (Dungeon Mapper?) they previously promised are not even mentioned."...After we launch our D&DI subscription service, the Character Builder will become our #1 priority. First up will be a public Beta test, then a commercial release, and then our development efforts will move onto the Character Visualizer..."