http://www.popularmechanics.com/technology/reviews/4258725.html?page=2

iMac | $1499 20"
Boot Average startup 28.7 sec.

Gateway One | $1800
Average startup 1 min. 13 sec.

MacBook* (Penryn) | $1299
Average startup 41.6 sec.

Asus M51SR | $1299
Average startup 1 min. 51 sec.

i dont think anything under 10-15 seconds is accurate.