Hey Again Bob,
Happily, I was able to catch Darren almost immediately. I have his permission to quote his replies on this topic. Very fascinating stuff here, I'm sure everyone will agree!
"Citation velocity isn't an issue. If I build 100 citations today, they will "go live" on the various sites at all different rates. 10 might get posted same day, some within a week, others within a few weeks, and others with months (or even years). So, citation throttling is naturally built in to the citation building process. I don't believe Google is measuring citation velocity as a positive or negative factor, but, the links can hurt you if you get too many at once.I have seen a case where one citation submission on one site spread to listings on THOUSANDS of other domains within the same business listings network. Rankings tanked.
"It's important to make sure you're submitting to quality sources. See: http://www.whitespark.ca/blog/post/12-how-to-identify-quality-citation-sources
"I think it's only a concern if you're not careful with the quality of the sources you're submitting to. You can only cause damage if you hit a site like the one I identified (it's a very nasty negative SEO source that I don't want to reveal). Building citations at 20, 30, 50, even 100 per day is no problem in my opinion because of the natural spread of when these listings go live."
Great feedback from Darren, no? I learned something today! I always learn something new whenever I talk to Darren and I appreciate the time he took to share his take on this with me. If anyone knows citations inside and out, it's Mr. Shaw!