First off, THESE PROBABLY WON’T WORK WITH THE EXISTING SIDEKICK 3. There, now that that is out of the way: Mobility Site is reporting that SanDisk announced a new 4gb miniSD card at the CTIA Wireless show.
The 4GB SanDisk miniSDHC card will be able to provide the fast speed and large capacity required to support increasingly popular but storage-intensive applications such as digital imaging, music and video record/playback functions as well as mobile television and videogames. The 4GB capacity can store more than 2,000 high-resolution pictures, more than 1,000 digital songs or up to 8 hours of MPEG 4 video.
The downside of this is that the miniSDHC cards are not compatible with existing miniSD card readers. But the good news is it sounds like all that will be required is a firmware upgrade to support these. This could be delivered in an Over-The-Air update (OTAu) to the Sidekick 3 quite easily one would expect. And Danger has until 2007 to get that update ready, as that is the projected release of these cards in the retail world.
More detailed info can be found in the press release here.