So I have a Win2k AD network.  2 cities. Exch 5.5 (on win2k servers) in both.I know there's no direct migration path to 2007. but here's my plan and the reasoning behind it.  Let me know if I'm smoking crack or I'm missing anything.

I'm going to upgrade the domain to 2003 AD first, by building new 2003 servers and promoting them into the domain. Reasign roles and decom the win2k boxes.

Then I'm going to install Exchange 2007 and create a new mail org. nice and fresh then I'll route all incoming mail to the 2007 box, and have it forward any addresses not found to the old 5.5 box.

Then I will slowly migrate users over by creating there mailbox on the 2007 server (so all new mail will arrive there) and export - pst - import the mail from 5.5 to 2007.

I have a total of 200 users (100 at each office)I know the export/import process will be time consuming, but I can do a couple mailboxes at a time, and I should be able to skip the 2000/2003 middle step this way.

Everything I read says 2007 can't exist with 5.5, but if 2007 is in a new org, and there's no AD connector on the 5.5 server, why would they care?

any thoughts?