Postgenomic.com makes use of the rel="conference" attribute for the <a> element. I'm not sure how they distinguish between upcoming and finished conferences (will need to check the source code). But I think some manual processing is done, for example, to extract conference details, like title, location and dates. I assume the URL is used as unique identifier. Additionally, the conferences are not 'tagged' yet, which should be possible too, as Postgenomic.com already associates tags from blog items with articles mentioned in that item. But this is likely a temporary ommision.
I already saw ChemConf2006 picked up from an earlier post by me. Unfortunately, because it is an online conference, it does not show up on tha map :( The following two conference do have a physical location, and I hope the will appear on the map. If you wonder why I mention only these two, they are the two I will attend in the next 8 weeks, and will have presence of open source bio- and chemoinformatics software developers (at least one, me).
- Netherlands Bioinformatics Conference, April 24, Ede, The Netherlands
- Workshop Chemoinformatics in Europe: Research and Teaching, 29 May - 1 June, Obernai, France