Actually, it is very simple: I had a slot in February. And one in May. Both are gone now. But because of the lack of anything stable-ish, I decided to use that slot for diving into some documentation on the proposed (and some submitted) changes to 7. And on getting stuff synched and tagadelic migrated to git(hub).
I planned a new slot in May. But again, there was no stable Drupal7 to work against. Off course, Tagadelic is simple, and could probably be migrated against a current unstable Drupal7, then work perfectly on release. But maybe not. And I really don't have time, nor the will to go shoot at a moving target. Nor do i plan to upgrade my sites to Drupal7 anytime soon: never fix something that aint broken: they run just fine on Drupal5 and Drupal 6. As soon as a client, who uses Tagadelic, hires me to upgrade a site, will I upgrade it and make it ready for 7. Or when someone steps up with a properly tested and clean patch to migrate to 7, will I commit it, or grant that person commit rights. In fact: you already have these rights: just fork tagadelic and upgrade to seven. Then let me know about it, to review the code.