This is really good news for a couple of reasons. In order to build universal applications that are both iPhone and iPad compatible it is going to require packaging more assets into the binary. This will make developers compromise less on quality to meet the 10MB d/l limit, which should produce higher quality applications.

And second, it shows AT&T is gaining confidence in their network. We will see if their confidence is merited as people start producing larger applications.

One potential down side is that if you buy the "cheap" 250MB 3G plan on the iPad you may have to wait to update your applications until you are near wifi.