Polk Audio previewed its upcoming I-Sonic ES-2 HD table radio at Digital Life Thursday. The entertainment system includes a docking station for all iPod models and is the first radio to include the iTunes tagging function, according to Dan Hodgson, senior vice president of marketing at Polk.

Tagging lets those with HD Radio receivers hit a special button to "tag" songs they hear on the FM dial, transfer those selections to their iPod and opt to purchase them when the device is synced with iTunes.

Apple worked with high-def radio technology developer iBiquity Digital Corp. to develop tagging. Polk has also worked with iBiquity on HD radio technology, so adding the iPod and iTunes functionalities to the ES-2 seemed like the "logical conclusion," Hodgson said.

ES-2 owners will be able to tag up to 50 songs at a time. The radio features four speakers for 360-degree surround sound, a remote control, video output and an LCD display. It will be compatible with all available iPods, Hodgson said.

The radio will retail for $499.95 and will begin shipping in the next three weeks, Hodgson said. It will be available at specialty stores, and Polk is working with Apple to also sell them at Apple Stores, he said.