From the Live Mesh blog:
Thank you for using the Live Mesh for Mobile client! For users who saw a failure to add their mobile phone to their mesh, we have deployed an updated build of Live Mesh for Mobile. You will need to download the Mobile Installer from http://m.mesh.com/install/wm6/LiveMesh.cab again. Once you have the new installer on your phone, run it and the installed client will be upgraded to the new version. The new Mobile Live Mesh Client is version number 0.9.3424.6 (check this through Menu -> About). Now you can start Live Mesh, sign in, and you should be good to go.
Sure enough, I installed it on my Treo this morning, was able to log in and start syncing folders. Synced folders can be on internal memory or the storage card, and open up in File Explorer when you click on them. Everything is editable just like anything else on your device. By default Live Mesh syncs your device with the mesh every 30 minutes, but you can change this if you need to.
My partner in crime on Maximum Geek wasn’t so lucky, though. He was told that there were a limited number of allowed users and was unable to register his device with the service. Now does that mean there’s a limited number of people who can connect at any one time, or that there’s a user cap on this beta? Let me know in the comments if you can get it working.
On the whole, very impressed so far. This is going to help enormously with NaNoWriMo, which starts tonight at the stroke of midnight!