The GPS lock is slow, but you learn to work around that for the convenience it provides, AGPS helps, so you just turn it on before you need it.

Personally I use my phone if I need a quick GPS lookup, and use the nokia for navigation.

The inbuilt browser is pretty slow. But install the webkit engine, or tear, or fennec, and that is mostly fixed.

Media - there is no accelerated graphics, so the cpu does the work. If you have lead time then using one of the various scripts to convert the files down to a bitrate / resolution compatible with the power available is a good move. Personally, I don't bother. Mplayer does a good job given the resources available, and video generally only gets choppy when there is fast action (so a higher bitrate).

Whatever method you use to get your video - recording off TV, downloading, ripping, you can usually automatically add to the workflow a step that creates a tablet friendly version.

These issues are manageable and dramatically outweighed by having an open linux based computer in your hands at all times.