Many people are wondering of this.
I have a theory about what's happening, which has all to do with the servers.
Basically, I think it's because of the recent power failures that Jagex has been having on the servers. Now there are two possible reasons why this is happening.
1. A lot of servers are down, so many more people are on each world them normally. This would also explain why F2p worlds have a worse predicament on their hands then most p2p worlds, due the the fact the f2p worlds are always full, while *most* p2p worlds are fairly quiet (compared to f2p

).
2. Jagex somehow is hosting the "Friends List" and the "Ignore List" on a completely seperate server, and due the the power failures, the certain server is very slow or damaged in some way, which means the actual RuneScape game itself is working fine on each server, but the lists are down.