In the interest of speed -- appropriate for the SPINN project -- the new Rendez Central web site was implemented rapidly on the weekend of November 10, 2011. The web technology chosen was an open source script called Elgg. This direction was chosen an an alternative to Buddypress, (based on the popular Wordpress blogging platfrom). Buddypress is functional, but the architecture with add-on modules becomes very complicated, and Wordpress seems to attract a lot of spammers.
Although Elgg seems to manage spam better (or at least differently) than Buddypress, I rapidly hit the wall on functionality. The Elgg community is small relative to Wordpress, and is possibly shrinking.
On finding "7 Modules That Will Turn Your Drupal Site into A Social Networking Phenom", the original platform for the Rendez site re-emerged as an option. Rendez.org started at Drupal 4.7, upgraded through Drupal 5, and has been stabilized as a legacy at Drupal 6. I was surprised that Drupal 7 functionality has taken a big leap from Drupal 6. The community is still active and supportive, so this looks like a better path than Elgg.
One test will be for blogging novices, as Drupal isn't as easy to use as Elgg or Wordpress. From an administration standpoint, Drupal has a lot of options that can be set.
The Rendez web site follows the spirit of SPINN. Sometimes the best way to advance is through learning-by-doing. Not all activities will be successful. We should look ahead to roadblocks, and may choose a different path if the outcomes are not as we expected.