The Santa Rosa platform will be compatible with the current Core Duo 'Yonah' processors and will also feature compatibility for the upcoming Merom processors along with an upcoming chipset called Crestine or Crestline (the name isn't entirely clear).
According to WinFuture.de, Crestline will be base on a 800 MHz FSB and integrate "Kedron," apparently Intel's codename for a new WLAN controller, which supports the upcoming 802.11n Wi-FI standard and apparently integrate the ICH8-M Southbridge.The Merom processor will be released in the September/October and the Santa Rosa platform is slated for March 2007. The Santa Rosa platform will stay around till the introduction of the Penryn processor, which will be the 45nm version of Merom. This CPU will be launched sometime in 2008.
Our own sources indicate that Santa Rosa will be built using Intel's 1263 process - the firms internal naming for 90 nm production of chipsets.