Despite the fact I've merrily been using my password since I signed up, when I changed my presentation today I got told that my password was 'too common' (which in itself is a little concerning, since I don't think it is) and the system made me change it.

Which has made me an unhappy bunny as I now probably won't be able to remember the damn thing. :P And we know writing down passwords and leaving them by your PC is a Bad Thing Indeed.

When was this system implemented, and why? Surely if someone managed to guess my rather obscure password, then that's my fault and mine alone?