(Woolwich) is a given, so doesn't count...
Chelsea: understandable, but they have other more local rivals (geographically) that they could consider rivals (Fulham, Q.P.R. Brentford...) I guess it doesn't help that 2 of those - Fulham/Brentford - are 'nice, family clubs' who plenty of people outside of West London have a soft spot for.
West Ham - again, I thought Millwall were their rivals?? Apparently not so much since they collectively decided to hate us more!
Leicester - just doesn't make sense... especially since they beat us to the title... if anything, we should hate them!
Southampton - Just weird (although Rupert Lowe didn't help with the whole Hoddle thing.)
Watford - maybe it's an ex-pat Woolwich thing innit?
I'm sure there are plenty of others, but I can't be arsed to waste brain power thinking of them right now!