SanDisk is cramming even more memory into its tiniest cards. The company today announced a 4GB Mini SDHC card designed to appeal to the multimedia cell phone user. SanDisk is promising that the 4GB cards hold up to 2,000 high-res photos, more than 1,000 music tracks, and up to 8 hours of video. Retail release is set for 2007. SDHC cards, or SanDisk high-capacity cards, have a capacity of 2GB or higher. Though the new cards are identical in size and shape to standard Mini SD cards, they are not backward compatible. As a result, Mini SDHC cards will not operate in devices with a standard Mini SD card slot.