I'm almost inclined to ask why VIA is, as reported by Impress, planning to release its dual-core Nano chip in 2010. By that point we'll have seen the use of dual-core Atom processors for over a year and, let us not forget, seen the release of the AMD Conesus chip.
Sure, in our VIA Nano vs Intel Atom head-to-head the former chip bested Intel's effort by a sizeable margin but Intel has won the arguably more important victory; market share. In fairness to VIA, the dual-core version of its Nano chip will have some performance enhancements, as well as being produced on a new manufacturing process. Both Intel's and AMD's transitions to 45nm have shown the benefits that can offer, so there's hope yet.
Initial chips will be available, presumably to interested system integrators, in December next year, with mass production estimated for June. Just don't get too exited. I fully expect Intel to have a 32nm Atom-successor, probably packing an integrated memory controller by then.