Oh no, sorry to hear about DS3. Hope everything is OK.
PR - basically, the current electoral system is hugely unfair in terms of the value of each vote. It's all very well to say 'one person one vote', but if votes aren't equal in value it doesn't really mean anything. As things stand, some votes (ie those cast in marginals) are a great deal more powerful/valuable than those cast in safe seats. Have a look at this site for a longer explanation.
I don't think what Clegg said just now was hugely significant - he has said similar thing for the past couple of days. Basically, if he goes into coalition with the Cons without getting significant guarantees on PR he's going to be seen by a lot of people as having been deeply dishonest.