I have two projects - 56056 and 9521 - but only the first will load, and quite rapidly at that. The second I have left spinning for a rather long time at least twice and it will not load beyond the "Loading Project" spinner. It was working perfectly yesterday, and I see no issues currently on http://status.rstudio.com/
UPDATE
The second project now loads like it did yesterday, but all the files and scripts have vanished! I assume this is just a bug and that they will return soon, but if there is something I can do on my end to fix this sooner rather than later, any counsel is much appreciated.
Hello - so I think that issue is related to the age of the project. There was a change that moved where people should be storing project data to /cloud/project. So the files are probably located off of your home directory I would take a look at: ~/, ~/R, or ~/project.
If they are I would suggest moving them to /cloud/project.
Brilliant! That was exactly the thing. I have now moved the files to where they need to be. Indeed, this was the older of the two projects and the directory was changed. It still loads very slowly, but it does load and the files are now 100% recovered. This is the analysis for chapter 2 of my doctoral dissertation, so I am very glad to have things back in order many thanks, @seans, you are a lifesaver!
I’m guessing you realize this but just in case — RStudio Cloud is still alpha software, so please please be making regular backups if you’re using it for anything at all precious!
many thanks, 
wise words!