1. This should not be a grounds to barrage WotC with a great deal of speculation and pessimism, unless you bought 4th edition for the sole purpose of D&D Insider, which I believe ought to be a fairly ludicrous decision on your part; I have not as yet bought any 4th edition source books, as I am testing the waters and reading up on all that stuff before I leap headfirst into it.
The fact that WotC is even attempting this is astoundingly impressive. I think it is exciting that around the corner (Probably sometime near christmas, nes pas?) there could be a professionally crafted virtual tabletop straight from the lion's den of RP gaming. As a DM who has left his friends and gaming group behind with a fairly large move, I can say that what WotC has given me by even announcing such a feature is hope.
I have a new gaming group now. We have fun, but most of them are new players, and I pine for the days of old when my experienced friends and I would stay up into the cold, dark hours of the morning, with half-lidded, sleepy eyes, rolling our d20's and knowing what was going on. The dungeon-making application that more or less goes along with the D&D Tabletop would make adventure-crafting that much easier, I'm sure.
So I do not think it is necessarily a good, understandable approach to be so pessimistic as to say "It'll never happen, they'll sweep it under the rug, blah blah blah..." because you never know.
2. I hope the Tabletop is more or less just dice, miniatures and tiles, with everything else to be decided upon later, as my group and I have always been addicted to the d20, 3.5 simplicity, and we may want to run a 2E campaign as well. It would be nice to have the possibility, and to remove the DM fudging and intuition would deprive the DM of a great deal of improvisation, such that the DM really wouldn't have as wonderful a game-running arsenal at his disposal as possible.
3. I think they will find that their prices may not be as high as they are planning, simply because at an outrageous, MMO price, no one will want the D&D Insider. They're already spending that money on WoW, after all.