Interestingly, the pronunciation seems to have deviated somewhat, but still doesn't come close to what you'd expect. So Worcester (and, of course, Worcestershire) would be pronounced 'Wooster', And Leominster 'Lemster'. Leicester seems to have stayed the same.

Of course, you've missed out the two most obvious strange pronunciations:

Magdalen: 'Maudlin'
Caius: 'Keys'

On the other hand, there's a town in Cornwall called Boscastle, and pronounced, strangely, Boscastle. Whenever I see it, though, I get the urge to pronounce it 'Bo'xle' to correspond with 'Forecastle'.