The two major questions are:
1) The current M777 (presumably A1) has an Accuracy of 10. What's the Accuracy of the A2/Excalibur?
2) Will the USA/USMC will use up their existing stocks of 155mm ammo and then use Excalibur rounds exclusively? If not the M777A2 should be a new unit available apx. 07/2008 and the existing M777A1 units should remain in the OOBs.
##############################
Excalibur was developed as a longer-ranged alternative to conventional artillery shells, with GPS guidance for improved accuracy. Excalibur has a range of approximately 40 to 57 kilometres (25 to 35 mi) depending on configuration, with a circular error probable (CEP) of around 5 metres (16 ft) to 20 metres (66 ft). The extended range is achieved through the use of folding glide fins, which allow the projectile to glide from the top of a ballistic arc towards the target.
Initial combat experience with Excalibur in Iraq in the summer of 2007 was highly successful, with 92% of rounds falling within 4 metres (13 ft) of the target. Its performance was so impressive that the U.S. Army planned to increase production to 150 rounds per month from the previous 18 rounds per month.
http://sill-www.army.mil/firesbullet...ages_14_15.pdf