Ok its been know for a while that AMD have been eyeing Quad Core chips, now its intels turn 
Its codename 'Cloverton' and will be on the Xeon platform
Cloverton is the lower end 4core Xeon it supports 2 socket mobos
the higher end chip will be called 'Tigerton' and providing support for 4socket mobos.
The comming out date of these chips is set to around 2007 ,,,but it is yetto be seen if intels take on HTransport [called CSI]
these chips are touted to be more or less two woodcrest Xeons stuck together
Woodcrest itself is based on the mobile arc as 'netburst' is no longer intels cared for baby
the cores work out @ bout 40 per watt [in current woodcrest protos but due to process shrinks this should becrease a bit]
Sources:
http://www.theinquirer.net/?article=29550
http://www.theregister.co.uk/2006/02/11/intel_clovertown/
http://www.pro-networks.org/forum/viewstory.php?t=70349
http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2006/02/11/BUGCOH6P2B1.DTL&type=business

Its codename 'Cloverton' and will be on the Xeon platform
Cloverton is the lower end 4core Xeon it supports 2 socket mobos
the higher end chip will be called 'Tigerton' and providing support for 4socket mobos.
The comming out date of these chips is set to around 2007 ,,,but it is yetto be seen if intels take on HTransport [called CSI]
these chips are touted to be more or less two woodcrest Xeons stuck together
Woodcrest itself is based on the mobile arc as 'netburst' is no longer intels cared for baby
the cores work out @ bout 40 per watt [in current woodcrest protos but due to process shrinks this should becrease a bit]
Sources:
http://www.theinquirer.net/?article=29550
http://www.theregister.co.uk/2006/02/11/intel_clovertown/
http://www.pro-networks.org/forum/viewstory.php?t=70349
http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2006/02/11/BUGCOH6P2B1.DTL&type=business