<img src="http://tctechcrunch2011.files.wordpress.com/2007/01/winter, but what's with the frequencies?
The new device operates at 850/1800/1900 MHz frequencies, whereas the Sidekick 3 operates at 900/1800/1900 MHz. Our own theory is that the upcoming Sidekick could be working with Cingular, which operates at 850, instead of T-Mobile, which does not. Or, it could just be a new version of the Sidekick which also works with the 850 band overseas, though we're not sure how many countries use 850.
The FCC confidentiality request expires October 12, so we'll find out more then.
New FCC documents posted [Hiptop 3]