If I had to be cynical, I would say that regardless of who you vote for you get the Government.

My earlier stance isn't altered despite reading some good erudite points in this thread in favour of AV.

As AV would mean more consensus (or horse trading as it is known) we have an example of that now. When confronted with election promises, Vince Cable points out that they didn't win so their promises don't count. The coalition feels it is not hamstrung by any manifesto promises. Now that's scary.......

We have this situation in a first past the post system, but my reading is that this is rare, although AV would make it more likely in any given election.

And that's why first past the post is the best of the bad alternatives. Not perfect, but not in a position to be replaced on the merit of the alternative.