It doesn't take long to build up MAC addresses in today's world. In my house I've got a PS3, Xbox360, LAN Printer, Wii, 2 Itouches, 2 desktops, 5 active laptops (several more retired), not to mention that I like the ability to allow guests to use the wireless.
I'm no longer using MAC filtering but I'm disappointed to hear that a "platinum" series router is limited to 24 MAC addresses.
Why would such a low limit (24) be necessary? Why not 256? Or 1024?