Greetings,
Somethings that should definitely be added or considered being added to Plesk for Windows:
1. The ability to add SPF records to the DNS. For those who dont now what an SPF is, you can read about it here:
http://spf.pobox.com/ 
It is another way to prevent spammers from getting thru your mail servers. Also, create a SPF record script so our subscribers can create SPF records before adding them to there DNS records. -- A DEFINITE MUST!
2. Zend Optimizer - include it with the Plesk installer so we can just install it with a new license on new servers that we deploy.
3. Like mentioned before, auto updates of php, perl, python, mysql etc etc to the latest stable versions.
4. The ability to integrate Window Media Services into each subscribers control panel so this option can be easily be made to them. -- would be a BIG PLUS! Also possibly Helix server [RealMedia10] as well?
5. SSL FTP server -- A MUST! Perhaps try to bundle g6 with it?
http://www.g6ftpserver.com/ Which I think is one of the best ftp servers out there. [my opinion of course]

And you would think with all that Microsoft has done in making Windows the way it is, they could at least make MSFTP have the ability to use SSL.
6. Include phpmyadmin root access from the admin control panel; and the ability to see what mysql process are currently running via the control panel [always a nice thing to be able to catch mysql abusers]
7. Maybe a choice of which email client to offer to our subscribers [horde, squirrel mail, neo mail]. Not a big consideration, just a thought. Ok that was just way too cPanel-ish
8. I might be wrong on this, but I noticed email logins are not thru HTTPS but rather HTTP, making it unsecure. Possible to change this?
9. I might also be wrong on this, but does Plesk have the ability to allow us to connect to the mail servers securely via SSL when we use a mail client such as outlook express? If not, would be nice to implement.
10. The ability to modify the DNS templates via the control panel itself. Also the ability to modify the default SOA records via the control panel.
11. I noticed IIS6 has webdav capability. Possible to implement that as well?
Well this is my list. Some things may be implemented already and I have just missed them, as I am new to Plesk. However, I am extremely impressed with the way it functions and operates on my first windows server. And If I think of anything else, I will let you know
