tedster - 4:19 am on Mar 12, 2010 (gmt 0) [edited by: tedster at 5:15 am (utc) on Mar 12, 2010]
If he can get legal permission to use a 301 redirect for even a month or two, then a Change of Address in Webmaster Tools might help speed this along. Otherwise all he can do is get the key backlinks to change over (which needs to happen no matter what).
I'm not sure that "rapid backlink growth" would be a problem for the new domain, as long as the content doesn't change. But there is likely to be a significant bump in the road.
[edited by: tedster at 5:15 am (utc) on Mar 12, 2010]