Snap! I was a size 12 in Next jeans for donkeys years and now their size 12s are huge on me. I've actually got one pair in a size 8 that fit me fine, the other couple of pairs i wear are 10s. I've lost a couple of pounds this year, but nothing like a dress size. I'm still a 10-12 in M&S clothes, and thought Next tended to come up a bit smaller but, at least as far as their jeans go, their sizing has gone weird and strangely generous.
Yes, I also think that their sizes are huge!! The clothes I already have from their still fit fine, but if I try on the same size in there now it is really big. I thought that they were supposed to be standardising sizes across the high street and getting rid of so-called 'vanity' sizing. I don't care what 'number' is in my clothes, I just want to be able to buy the same size in all shops!
Pollyblue, same thing here with their jeans! My normal size that I buy in every other shop is ridiculously baggy in Next!