1. It is lower resolution than the IDT-700.
2. It is a smaller screen then the IDT-700.
3. It doesn't fold up into the dash like the IDT-700.
4. It doesn't allow other types of input such as video like the IDT-700.
5. It only has 4gb of memory for your music.
6. The OS appears to be locked down, preventing customization or other alteration very easily
7. It only connects to the net via WiFi. For mobile connectivity, you have to bring a phone and data plan.
With a screen so small, why not simply use a Windows Mobile or iPhone instead? Both can have their functionality expanded via applications or apps, both have more memory for music and both have screens that are only slightly smaller than the MiND for just slightly more. If the cost is an issue, an iPod touch can be substituted.
A netbook can also be had for about the same price while adding much greater flexiblity and expansion capability.