Which AM2 MBs allow drop in Barcelona upgrade?

[imported_ITguy]

OK, I've recently read reports that AMD claims their forthcoming Barcelona quadcore is 40% faster than Cloverton (2 core2duo's linked together). Now assuming that this is true (only an assumption), which motherboards that exist today (or upcoming) will allow a drop in K8L (K10/Barcelona) cpu with a potential simple bios update?

Is it only the 4X4 motherboards or will the newest AM2 boards support the Barcelona core as well?

Thanks.