As of the past few days, the GPX driving directions and poi web service hasn't been working for me. I had just flashed my n800 to os2008, so I thought that might be the problem, but when I tried using the browser interface I got the same problem. No matter what querry I sent it claims the source or destination is invalid, even the exact same sources that it accepted this time last week.

Have others observed this as well? Perhaps Google simply changed the format of itsresponse pages causing breakage.