This is something that I have also been following up and they keep telling me in the next release. We have a fair amount of servers that we want to migrate away from Parallels Pro X (formerly Ensim) to Plesk 9.x. The sooner they release this Migration Manager the better for us and them as will be making $2,000 from our Plesk subscriptions from us. They have already lost 10k from us by not releasing it... they own both products so it could not be that hard, its not as if they need to reverse engineer Ensim to figure it out.
I went to the Parallels conference in Vegas in Feb 09 (from Australia) only to get some questions answered that I could not get answered via the normal support channels, the two main questions I had was how to get our Modernbill 4.4 database migrated over to PBA (Parallels Business Automation) and the Ensim 10.x to Plesk 9.x migration.
I dont know what they are doing with all of these Control Panels the have just aquired but from speaking with Serguei Beloussov who is the founder they have big plans. I got the impression that they are going roll all of the legacy CP's in to one best of breed CP and im assuming they will be using plesk as the flagship base CP.
I have spent some $13,000 (not including my casino fun) on the trip and I just was fed with empty promises. Once we had figured out that their PBA migration script was totally SH*T and only 20 percent complete and didnt import anything useful we started writing our own which has now taken 3 months and cost $18,000 so far but it's a few weeks away from completion (we are in the testing stages) now and imports everything..
One good thing that came from the trip is the fact that I has met a few Parallles engineers and kept in communication with them, they have helped us with a few major issues. This whole PBA saga has cost us $31,000 to date. We may have to sell Parallels the migration software once complete, they will get a lot more people migrating if they has something that works. It seems that PBA is an excellent product to use for billing if you are just starting and dont have any customers or very few that would be able to be migrated one by one.
So I will reinterate the question asked by the original poster. Where is this Parallels ProX to Plesk Migration Manager? The quicker you release it the quicker you start getting $$ from me....