We got this e-mail from a reader who obviously knows a lot about the subject. We will say though that we have used AVI cards and have had no complaints. But we defer to his superior knowledge.
Please do not recommend ATI capture cards. They make fine videocards, but unfortunately that makes people assume their vidcap is worthwhile too. It's not, and never has been. They no longer make as many proprietary chipsets like in the Rage Theater days, but you still cannot use 3rd-party drivers with any of their cards except the Conexant BT8x8 (ATI brand name "TV Wonder VE"); manufacturer-provided drivers and software always suck, and ATI's suck worse than most.
Thankfully, HDTV capture cards are not rare. You can get something nice like a MyHD for around the same price. Their tech is also much more mature -- it's a newer revision of the same HD chipset I was using to cap the 2001 FF.
Do buy while you can, though. Starting 7/1/05, it will be illegal to manufacture or purchase digital TV cards (HD or not) as we know them. Unless the FCC changes its mind, "broadcast flag" regulations mean the end of video interfaces to PCI, PCI-E, PCMCIA, USB, etc., and even if computers start to support HDMI you'll lose a lot of functionality.