"SanDisk Corporation today introduced a 4-gigabyte SD High Capacity (SDHC) card. The new cards, which support capacities of 4GB and higher, are rated Class 2 for speed and performance and 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 4GB SDHC card will be bundled with the MicroMate USB 2.0 reader at no extra charge. These new readers work with both SDHC and SD cards. SDHC cards require an SDHC-compatible reader." Larger sizes are always great, but I am betting there will be a little confusion regarding compatibility of these at first. For the most part, these cards are not going to work in your current SD compatible products.