Should I use the SP1 cross-site moves?

First, my apologies to the folks I'd planned to grab lunch with while I've been out in Redmond these past few weeks. The project I'm working on has been keeping me much busier than I had expected. Maybe next time!

Onward -- Someone commented a few weeks ago on an earlier post:

a question about site consolidation: I have a couple 5.5 single-server sites in my org. Is it best to use the cross-site move method described in your webcast, or can I simply install the 2003 server in the single-server site, move all objects, then once in native mode move the server to the appropriate Admin Group?

Well, you can't move the servers between Admin Groups, even if you're in Exchange Native Mode. But this is a pretty good question, really, if you look at it from the "moving objects" perspective. The new SP1 Site Consolidation feature is great, but it can also be pretty complicated to execute, even with the appropriate planning. Maybe the old way of doing is still suitable in some cases?

The two generally available consolidation methods are:
1) SP1 Site Consolidation - Do planning, meet prereqs, use the new tools to migrate while still in mixed mode.
2) Native mode Site Consolidation - Do planning, meet prereqs, switch to native mode and then move stuff.

Ok, so that's a bit of an oversimplication. But at the core, the decision is one each customer must make. Prior to SP1, there was only the 2nd option.

The most obvious characteristics of this second option are:
1) Have to install additional servers (need an E2k/E2k3 server in each 5.5 site). This is possibly not a small problem -- if you have hundreds of 5.5-only sites, adding an E2k/E2k3 server into each is HUGE!
2) Your mixed-mode infrastructure may become VERY complicated. Remember, you'll be administering a parallel Exchange 5.5 and Exchange200x/AD environment right through until you go native mode. This may have large admistrative or bandwidth implications.
3) Once you've removed all 5.5, followed by removing all SRS, etc and switched to native mode it's actually fairly easy to do your consolidations. You can use the move-mailbox GUI in native mode to move mailboxes between administrative groups. Public Folders and DGs/Contacts are likewise no longer bound by the AG once you're in native mode.

For smaller installations of Exchange 5.5 (say, a handful of sites), this might make the most sense. The planning is a bit less, and the prereqs a bit easier to meet.

But for larger Exchange installations, it becomes more difficult to justify implementing additional servers in remote locations right as you're being asked to consolidate existing servers. If this is the case in your environment, the SP1 Site Consolidation feature may be for you.