iMac AL 2.66Ghz 20" Upgrade RAM

Hey guys,

I just bought an iMac 20". It came with 2GB RAM and I want to upgrade to 4GB. On my old iMac, upgrading was easy, PC3200. Now, is it like notebook RAM? or 168? What? Could someone recommend a 2 x 2GB ram package from say Newegg? Thanks!!

$68? Thats great! I remember paying close to $100 for a 512MB. Also, is crucial better then say, Kingston? So Crucial is the best brand for this?