I've looked briefly in this community and haven't found it, and it doesn't really affect my decision to go ahead and upgrade to MC from Xpress Pro...

But can you mix 720p and 1080i in the same timeline with the new MC upgrade or is that still a no-no?

Also, can MC monitor and output 720p at this point?

If that answer is no, I would ask the community their thoughts on the best workarounds...I'm cutting a 720p project but need to integrate 1080i AND get it to play back for the client monitor AND eventually output to tape.  Do I have to reconfigure everything to 1080i AND/OR cross-convert my 720p tapes?

Any ideas on how to do this efficiently are welcome.

You cannot mix progressive and interlaced footage in the same project at this time.

I would suggest picking the format that has the most footage, and using a deck to cross-convert into the other format.  Most decks should be able to do this for you.

The Avid will monitor almost all flavors of HD, including 720p and 1080i.  Even 1080p if your monitor supports it.

You said "the Avid"...which I assume means Media Composer...will monitor 720p which is good because Xpress Pro does NOT monitor 720p nor will it do a Digital Cut of it.  I'll read up on it more to make sure but thanks for your input...

Yes, I was referring to Media Composer (I'm not familiar at all with the XPress line of products).  And with XPress at the end of its life, you will probably need to consider upgrading at some point if this is going to be your workflow.