One of the main reasons new edtions don't bother me is that I
haven't invested all that much in any one edition. Of course, one of the reasons that I don't, is that I expect new editions. It is rather circular.
It wasn't a choice with 1E and Basic. I got a handful of things that I could afford in my teens, and then picked up the RC later. With 2E, I mainly opted out, until I bought some of the FR supplements (late in the cycle) for use with Fantasy Hero. With 3E, I got the core rules, and a handful of the first round of supplements, and then some selected third party stuff. (And some of these, I picked up for $5.00 each in close out sales.) I own one 3.5 book. With 4E, I haven't even got the PHB 3 or MM 3, much less all the supplements. (I think I have two.). I've got 2 or 3 Essentials books.
It's a lot of stuff, collectively. But it isn't overwhelming. I'm the same way with any system I get into. My theory is that not every book in the line of a given edition is gonna be a killer product.
But I still think if WotC wants to double-down on DDI, they should do the game first in DDI, with a Beta, and then subscriber-only play. Then when it is humming like mad, print a set of books that incorporate the best of play. Get in early; do it their way. Or wait a bit, and get the best material of the edition.