Several users with large bookmark sets have contacted us to say that they were unable to view their bookmarks on my.foxcloud.com because our server was running out of memory.
Now that the Foxmarks extension seems to be heading towards stability (fingers crossed), we finally were able to spend some time today looking at the problem with my.foxcloud. It turns out that the parser we grabbed off the web, while complete and accurate, turned out to be a total memory hog. So we wrote our own, and life seems much better now. In one our test cases, we reduced memory usage from 100 MB to 8 MB.
So, if you've got a large set of bookmarks and you've been denied by My.Foxcloud in the past, head on over there, give it a shot, and let us know whether it works for you now.