All this tinkering with the IFIS lovemap of doom has got me pondering trying to fix the flawed and broken Facebook version. (And possibly the LJ one too. Which I don't think is broken, but possibly could be)
The main problem with all the many versions is the reliance on each user having a password. The password is used to generate the anonymised ID that represents people on the lovemap and encrypt your information. If you forget the password, then it can't tie you to your ID any more and if you use a new password, you get another ID. Which means that you can end up with a lovemap that involves just 2 people, but has dozens of blobs.
Which is pretty much what has happened on the FB version - there are apparently 2000+ IDs in the system and IIRC only a few hundred actual signed up users. The urge to wipe all the data, remove the need for a password and store everything in clear text is very strong right now. Or maybe have some kind of migration process so that at least some of the data is kept.
Either way, I think this weekend is going to involve a lot of tinkering with code.