Have you tried closing Visual Studio in between? It won't update until after you close. I've also noticed that if you have 2 or more Visual Studio's open at once, it won't always save your project to the MRU (most recently used list).
You can check out your options for how many to dispaly in case it's 0, but the default is 4 I think: Tools->Options->Environment->General and look for "Display ___ items in most recently used lists". 20 is the max and works for me.
-ner