Google is planning to release Android 2.0, i.e. Donut, in three to six months. This announcement was made by Google at the recently concluded Google I/O in San Fransisco. That means, it would release this year itself. That would mean two version releases in a single year.
According to Andrew Rubin, out of the 18-20 Android powered devices that was supposed to be released this year (click here to view the post), some would probably release with Donut.