My brief in the New York Times on Roku's upcoming Internet radio tuner: It's an interesting device and I can't wait to get my hands on one for review in a month or so. I found out a few interesting items not mentioned in this brief from interviewing Roku's founder. Because they aren't using a computer (PCI) bus, their choices for Wi-Fi chips are limited--that's why they are using Philips 802.11b chip with WEP-only drivers.
The WPA drivers are in the pipeline, and the unit could ship with them, but it's unlikely. However, since this is an Internet-connected device, a software update will provide the WPA support with little effort to push the new firmware in by the user. (I wish someone would hack up a $50 WEP bridge with extreme firewall settings for WPA-only networks that want to use WEP-only devices.)
Also interesting is that HD Radio (digital AM/FM) isn't anywhere on Roku's radar because Internet radio effectively displaces the need for HD Radio--for stations that stream simulcasts, at least.