In this article, Google and Yahoo accept undelayed meta refreshs as 301 redirects, Yahoo is quoted as follows:
" META Refresh: <meta http-equiv="refresh" content=...> is recognized as a 301 if it specifies little or no delay or as a 302 if it specifies noticeable delay."
And the same article quotes Andrew Adam Lasnik as saying
[The] "best idea is to use 301/302s directly whenever possible; otherwise, next best is to do a metarefresh with 0 for a 301. I donít believe we recommend or support any 302-alternative. "though I couldn't find that quote on Lasnik's site.
Perhaps some of you have recent experiences using a Meta Refresh with 0 or can point us to a definitive answer from Google on this - though everything I read suggests Google has not addressed this question.