Has it never worked for you since the patch?
This is whats so frustrating one day it works fine the next it does not. Whats even more confusing is that sometimes it will capture the loot given out but not the raids.
Here's the thing to test.
1) Form a quick raid with a few random guildies
2) Take a manual snapshot (ie: /grss mytestsnapshot)
3) Log out of WoW and try uploading the snapshot and see if it's there.
Tried this just now and everything appears to work fine this way.
Keep in mind that if WoW crashes at all (or you ALT+F4) before the data is written to the hard drive, that all those changes are lost.
What normally causes the data to be written to the hard drive?
Try typing /console reloadui after snapshots to force WoW to write the data to the hard drive.
If /console reloadui will force it to write to the hard drive I can see doing a lot of this from here on.
If the snapshots are being taken in-game, but the data isn't there, then what's happening is WoW is failing to write it's mod data to the hard drive. The most common cause is WoW crashing.
Again no wow crashes last night, what else could be causing problems?