There seems to be a bug in the My Models page as models I've deleted keep on showing up. They are listed as Not For Sale and don't have a picture associated with them. Also clicking on the model leads to a "Page Not Found" error. This suggests that the models have been deleted but some information has been missed. What's even odder is that if I delete them again then they disappear for a while only to re-appear later.
Example model numbers (in case they'll help to track down the problem) include: 896820, 903252 and 903343 -- these are all private models but anyone debugging the issue should at least be able to use the numbers to check the underlying database to see what's going on.