According to Fangoria.com, filming on the AVP sequel will begin on September 23 and finish December 14 in Vancouver, Canada. The website writes:

AVP's Tom Woodruff Jr. and Alec Gillis of Amalgamated Dynamics, veterans of the first AVP (pictured) and all the previous ALIEN sequels, will encore on the creature FX. The Shane Salerno script places the battling extraterrestrials on U.S. soil (the Midwest); FX pros Colin and Greg Strauss make their feature directorial debuts on the December 21, 2007 Fox release.

20th Century Fox has already set a release date for Alien vs. Predator 2 on December 21, 2007.