The similarities and strange between the two, so here goes giving brief reasons

Darren = Alex -Constipation
Nigel = Jonny - wants to get own way
Uri = Sandy - control freaks
Tony = PJ - blokey and matey

Christine = Adele - 2 faced
Nell = Jade - dumb blondes
Rhona = Alison - loud, in your face and irritating
TPT = Sophie - Wannabees getting bullied

Wish I could comment on this but I never watched BB3 (apart from the mind-numbing live coverage I saw on E4 when I watched some dude search for a pair of scissors for 15 mins).
I watched the first BB (Summer 2000) religeously but after that I completely went off reality TV - you have to admit, it is pretty crap.
Apart from IACGMOOH and Cruel Summer/Winter on Trouble TV, I can't stand reality shows.
In fact, I didn't even have any intention of watching IACGMOOH untill I found out Rhona Cameron was gonna be participating and the only reason I watch BB1 was cos Anna ruled!

Comparing Nell McAndrew to Jade!

In the first few days of BB3 Jade couldn't keep her gob shut, she was all you can hear all day, I don't think I've heard Nell say even one word

And Rhona like alison, Alison was always laughing about something whil rhona has a permanent face like a slapped arse