probably better then England.
Spain:
Camp Nou (96k i think) and Bernabeu (about 80k), and they are building Nou Mestella in Valencia (75k), espanyol has a new stadium of 40k seats. then there are 2 big stadiums in Sevilla, both +40k, and athletico madrid and athletic de bilbao are around 40k i think.
then there is Portugal who have a few awesome stadiums ready from their european Cup ( benfica, Porto, sporting)
belgium and Nederland have exactly 1 stadium ready (2 others are big enough though but those will be rebuild). and i don't know what we would do with all the big stadiums after the WC.
edit: sevilla has a stadium of 45k and one of 52k seats, and athletico madrid has 55k-seater