Fourteen years ago, devotees of WXYC, the college radio station of the University of North Carolina at Chapel Hill, fired up their computers and tuned in to the world's first radio signal to be broadcast over the Internet. Now about 13 percent of Americans listen to radio online -- still well more than those who subscribe to satellite radio. Here's what we broadcast this week:

• Social buzz: Yahoo! Buzz is the latest to get into the open game. A new Updates section on Yahoo! Buzz lets you keep track of stories that your friends have buzzed up or down. Also new is a "Comments" section for individual stories so that you can weigh in with your own opinion and further the conversation. What's more, you can give a thumbs up or down to other people's comments, or reply to them. Lots of opportunity to mouth off! And you'll find a personal activity hub for each of your contacts (provided they want you to see it) so you can check out their voting and commenting history.
• Take me to your leader: The next POTUS might still have 73 more days before he takes office, but it's not too early to send him a presidential communique -- via photo. The Guardian has set up a Flickr pool for people who want to send personal photo messages to Barack Obama -- whether you want him to end the war, fix healthcare, adopt that puppy, or prove you wrong. It's worth a thousand words.
• Cinco de delicioso: A big happy 5th birthday to the team at Delicious (or Del.icio.us, for you die hards). But that's not the only number five to be celebrated. They now boast more than 5 million users, all of whom have civic-mindedly saved more than 180 million unique URLs. Cupcakes all around.

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