1. I created a test project in Project 2007 with 3 tasks in it (task a, b, c)
2. I took a backup of all projects through Server Settings --> Administrative Backup
3. I added some time (through My Tasks) to task b, and changed the overall remaining work to 40hrs
4. I approved the task update and then added some tasks in MS Project (tasks d and e)
5. I published the project, saw the changes in Project Center
6. I then restored the project using Server Settings --> Administrative Restore
7. In Project Center it still shows as the last published (i.e. tasks a through to e), but in MS Project it shows as the original project above
8. In My Tasks, it still shows as the 40hr task with actuals against it
9. I published the (restored) project from MS Project
10. In My Tasks, it still shows as the 40hr task with actuals against it, until I actually click into the task (e.g. click on the task name), then it goes back to an 8hr task

This means that a restore will not only get rid of actuals, but also any added tasks (which is what I would expect)