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I appreciate your help. I saw the SEOmoz article this morning, thought it was appropriate Andy

Some good advice from Google on changing domains here: https://www.google.com/support/webmasters/bin/answer.py?answer=83105&hl=en I have never 301'd 50 different sites either, however I wouldn't just leave it up to the 301s to inform Google - use the 'Change of Address' function in Webmaster Tools.  If you haven't already got Webmaster Tools set up on all of the old sites, I'd say that's an essential task to do first.  Then you can tell Google manually that the new site is replacing the old one/s.  You'll have to repeat the process 50 times but it's quick, easy and well worth the effort. Google suggest that you leave the 301s in place on the old site/s for at least 180 days - but probably better to listen to Marcus and Alan; 12 months won't do any harm. I'd also get the new site up and running concurrently for a few weeks first, if it's a new domain or if it hasn't had any content on it for a while.  A client recently immediately killed their old site upon launching the new domain, found out the new domain had previously been burnt, and it tool 6-8 weeks to recover rankings for the new site after a 'reconsideration request'.  It cost them organic traffic and extra PPC spend. Maybe others would advise against this?  Realise it's potentially duplicate content but a short cross-over period would enable the old sites to continue providing temporary value as the new site registers.

Quite correct.  I unfortunately assumed that everyone already knows this bit of information.

Definitely go for the one domain approach in a bid to create a larger digital footprint, I too used to have multiple single domains targeting a keyword or two and now after the last Google Panda update these keyword rich domains aren't as effective as they once were.