Esoos - 1:29 am on Mar 23, 2012 (gmt 0)
Thanks for all the helpful feedback. I believe I'll use both the zero-second meta refresh and the canonical tag in combination.
Regarding leaving the content up on the old site and changing the links to point to the new site, I'd be concerned about creating duplicate content problems, since the content will still be up in two locations (although we could meta noindex the old pages).
Instead (as was suggested) I think I'll pull all the content down from each of the old pages and just have a short message on each page (for browsers that don't refresh and for search engines) that says "This page has been moved" with a link to the new page.