Hello Guys. I work for Linksys and I've been given this link by some customer. Hope to help you with port forwarding, port triggering or DMZ.
As for the wireless disconnection issue. It may be a design flaw by Sony. The integration of Bluetooth controller and Wireless technology is questionable. (I'm not that sure, though.) Bluetooth and Wireless (B/G and N) are operating at the same band (2.4 GHz). That would mean that using both at the same time will eventually cause wireless interferences causing the dropping connection.
This would explain why other wireless computer can connect just fine without some problem except for the PS3.
I'm not that sure with this, though. I suggest that you try using the wireless connection of PS3 to your router while the using a wired controller. And check if the wireless connection drops.
I'm a game addict myself. I was planning to purchase PS3 this christmas holiday but I'll have to wait for your findings. heheheh ^__^
If you need help with the configuration of your router, I may be able to help.