We are experiencing intermittent performance issues with RStudio Cloud. Under heavy load (i.e. when many people are using the system), it may take 5 minutes (or more) to create or load a project. We are investigating the problem and will update this post with additional information as we have it.
For now, we can only suggest that you be patient if a project is slow to load, or try again later when fewer people are using the service.
We apologize - and thank you for your patience.