The drawback to the Dell Mini 12 is that it comes (stock) with 1GB of RAM and Windows Vista.
You might want to take a look at the MSI Wind. The price tag is in your range, and it comes equipped with an old-fashioned harddrive instead of SSD, which means you can get 120GB harddrive, and you'll probably be in your price range. As of this past week, you could find the Wind for $350-400. The ones closer to $400 come Bluetooth enabled. The less expensive ones don't have it.
The MSI Wind also has one of the largest keyboards of comparable sized netbooks. It's not full-size, but it's closer than the Asus keyboards. Haven't a clue about how well the touchpad works.