The Tosiba AC100 smartbook is going to be the first smartbook to be available on the smartbook space. It is available in Japan but it seems Toshiba UK is also planing to offer the AC100 soon.
Detailed Specification : http://www.smartbooktalk.com/smartbook-news-reviews-f4/toshiba-smartbook-getting-its-way-into-the-smartbook-space-t290.html
The UK model is said to have 128GB of solid state disk and 512mb of RAM.
The tweet is available here : http://twitter.com/ToshibaUK/status/21586274400