It's not the the advent of 720p webcamming that we're seeing here—it's just a change that means that it won't have to look like this, and will probably come built into mainstream notebooks.
Samsung's new 1/4in CMOS sensor is claimed to produce a 720p images at a full 30FPS, and VGA (640x480) video at 60FPS. Samsung manages to preserve low-light performance at such resolutions and framerates on such a small sensor using a technique called "binning", whereby certain pixels are sometimes deactivated and grouped together to help gather light for active pixels. In other words, if you're, uh, Vlogging in the dark, your webcam stream might look like it's 720p, but in reality a significant number of pixels might be clumped together. But at least you'll be able to see them.
The sensor was designed with integration into laptops and desktops in mind, and should go to manufacture in the first half of '09. [Samsung]
Note: actual sensor not pictured