The Hitachi CP-WU8451 supports full HD, which is unusual. Most of the other 5000:1 contrast ratio multimedia projectors that were launched more than two years ago do not support full HD.
There are a number of other projectors which support full HD currently available which you might want to consider including cheaper multimedia projectors such as the PT-VZ575, or the PT-VZ570 both from Panasonic.
There are a number of other projectors which also support full HD which you might want to consider including the NEC PA522 (£1,999).
What is full HD?