Being a Mac user and a DDI member since day 1 I'm not terribly disappointed with the new CB. On the first day, yeah, it was a buggy sack of crap, but it seems like its gotten better as time goes on, for some reason. Since Day 2 I've only had one error message, and that was because two people were trying to work on it at once. I also like the interface better than the Old CB's cluttered "twitch and you buy it" design.
As for Dungeon and Dragon, I have to agree largely with those here. I don't need adventures or DM advice, so Dungeon is dead content for me, and as for Dragon... Well, actually, if we look this month, things aren't that bad. We get several new articles improving various classes, some of which were either very well written (Cultures of Nerath) or cool mechanically (Cavalier Mounts). My only problem is that very little of it will get used by myself, since I doubt I will use many of the Essentials classes and that's where the content is unfortunately focused. It is a vast improvement over last month though, where the only article of note was a rather o.k. one on fey themed wardens and a balls overpowered one involving Illumian themed boons. I have noted a great decline since around 380 though, but there are still diamonds on the rough.
As for Dark Sun in the compendium... that sucks? I doubt they arbitrarily plan to withold the content from us (if they did, why add in the class material?), as it just makes no sense. I know most people are still stuck in torch and pitch-fork mode over the new CB and many others can't comprehend WotC not being incompetent/evil, but come on now. Chances are they just got caught up in all thise other BS and forgot about it. For me the Compendium is still very much worth it, Dark Sun or not. It makes DMing a breeze and character building easy if, like me, you didn't have the character builder for three years now. Without it, adventuring building would be an epic pain in the ass. That in itself was enough for me to resubscribe when my sub lapsed due to credit card issues.
All in all I still think things are of value. Maybe not as much and maybe not as often, but I'm still paying my subscription to get what value there is.