I finally actually installed dropbox to see how it happens.

Ran into another problem. That registry data does not seem to update on the fly. Did a RegShot with dropbox up to date, and then ran another when it was syncing files. It did not find any difference.

In fact Dropbox didnt even show up in the decyphered registry value until after I rebooted.

So all of this may be useless. Of course it may update differently on newer OS's. But I only have XP here.

But as far as what it displays, it will either say...
"Dropbox 2.6.33
Up to date" or it will say something like...
"Dropbox 2.6.33
Downloading x files (x,xxx KB/sec, x mins left)"