SiS chipsets may not be as exciting as the latest ICH or NV chipsets, but they certainly have come a long way from the bargain-bin chipsets they used to be years ago. Given their strong presence in the entry-level market, they are important for many people. Their newer 680 series, which will bring many nice features such as 1333MHz FSB support and their newer IGP engine, is schedule for a release before the end of this year.
The 680SCE, 680SCP and 680SCD are at the higher end of the SiS spectrum, which will support DDR2-1066 and DDR-800 memory. The SCE's IGP will support HDCP, though it isn't mentioned if they will have native DX10 support or not.
The lower end will include the 680SCH and 68SCL, which will not have 1333MHz FSB support but will still support DDR2-800 and DDR2-1066 (SCH only).