let's be honest here, noone would expect something "affordable" from Apple, they are a premium brand. It's like BMW coming out with a ~12,000 car....just won't happen.
The multi-touch is sexy, i'll admit. but form is not greater than function. Imagine chatting, posting on HN, or uploading photos to Flickr. These 3 easy actions are not easily handled on the ipad.
<edit> I have never used it and cannot comment on the build quality (which is the point i was trying to make. Sorry!)
Unfortunately, it's not possible to get the large screen and a 3G card together. Or the higher powered CPU and an OTA tv tuner. In fact, it's pretty impossible to build a decent dell mini-10 system, so forget I even mentioned it. Or don't, and remember not to spend ten minutes futzing with their customization workflow...