I am an engineer too, but I have drifted into infrastructure asset management over the years.
I joined MuniGov a month or two ago. I've posted a couple of messages to the google groups mailing list, and just yesterday I added a glossary page to it and added a couple of entries. http://sites.google.com/site/munigov20/glossary. I have yet to venture into second life. I like google groups as an option for the mailing list, but I don't think that google sites is all that good an option for a public knowledge base. It would be great if you can encourage someone to set up something up for US Local Government, and I am happy to help if I can. My site is hosted by Wikidot ( http://www.wikidot.com/ ) which I think is a good option, but a MediaWIki based site, or even a PBWiki based site like the Sub Council on Social Media site could work just as well.
I notice Steve has mentioned a couple of sites (Crunchbase & Govitwiki) in his post. I will have a look at them and post an update later.