Marval - 1:00 am on Jan 20, 2005 (gmt 0)

The other factor is whether the new domain is really a "new" domain or one that already had content and was indexed.
I'll let you know my experiences as I just redirected 5 old domains that mistakenly got indexed as dupes of my main domain and they just got 301s replacing the old aliasing that they were under.