The main problem that was slowing down Intel's DDR3 only boards and AMD's AM3 boards was the fact that DDR3 memory was really expensive and this statement is not true anymore.
Newegg in the USA has an amazing offer where you can buy OCZ Special Ops 2GB (2 x 1GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Dual Channel Kit Desktop Memory – Retail kit for just $23.99. You need to pay $43.99 now and after you send mail in the rebate voucher, you will get your $20.00 back. You can buy it here.
If you want more performance you can buy OCZ Gold 2GB (2 x 1GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Dual Channel Kit Desktop Memory – Retail kit for $42.99 after $10.00 mail in rebate and with these prices, there is no room for complaints about the high price. You can get this kit here.