Intel is moving very quickly into an all dual-core lineup, getting ready to offer dual core Xeons, Pentium 4s, and Celerons. They aren't abandoning single-core processors just yet, though, and the Yonah core will see another release within a year for budget laptops and perhaps budget desktops
. Of course “budget” meaning “cheap” in this aspect. Like the development of the Celeron, it seems that all Yonah core may be dual-core, but single-core varieties will simply have the second core disabled. This is very common in the PC industry. The top clock speed for the Yonah isn't known yet.