D&D Red Box: not compatible with any other product.
So? It wasn't like the original Red Box worked with AD&D either.
D&D Essentials: so much confusion as to what it is and who it is for.
I kind of hate to say this but... I think we created that confusion ourselves, talking ourselves into a kind of frenzy of speculation, rather than just looking at the product and letting it speak for itself.
D&D Insider: a worse disaster of implementation is hard to imagine.
Um, really? Hard to imagine? The software field is heavily loaded with far worse rollouts than WotC has had. "Vaporware" is a term for a reason.
On the contrary, it seems to me that WotC is on a steady (if slow) course of turning themselves into a company that does software vaguely intelligently. Think back to their previous forays into software: the CDs that came with the 3e books, the stuff that was supposed to be available for 4e's release but wasn't.
Have there been mistakes? Sure. But we are talking about a company that is converting itself from plain print publishing to software, without also dropping it's original core business, and (I assume) doing so without blowing budgets completely out of the water. That is hard, hard stuff to do. They are in the midst of a massive learning process, with a steep curve. If you expected something near perfection, you were kidding yourself, and that's not WotC's fault.
And, honestly, it seems to be working. Slowly, the beast slouches into the 21st century!