Not so fast -- firstly, there's been some coverage of the "Maemo 5 device" on gadget sites, so many of the in-the-know potential early adopters, if they liked the N810, but wanted HSPA, may wait a couple months to see the RX-51 announcement before ordering an Atom MID. (And certainly existing N8x0 fans...) Second, many people are aware of the poor battery life of the Atom, and waiting for either the AMD competitor, the next generation Atom, nVidia's Tegra, or whatever; they'll still be shopping when it's announced. And then there's all the people who, for whatever reason, choose not to buy MIDs immediately, even though they want one -- including those just short on cash.

Nokia can pick up all these customers, who I think outnumber the early adopters you're considering.
They've given up an edge they could have had, but they're not at all far behind, and even if they were, it's in no way insurmountable. Asus was the first with netbooks, but late entries (who were caught flat-footed!) do compete successfully as long as they are better (or cheaper). I see no reason to think the MID/IT market is different that way.