Just an hour ago comScore released the U.S. search engine rankings for September. Without further adieu here is the lowdown on the search engine wars:

September 2009 U.S. Search Engine Rankings by comScore

* Based on the five major search engines including partner searches and cross-channel searches. Searches for mapping, local directory, and user-generated video sites that are not on the core domain of the five search engines are not included in the core search numbers.

Americans conducted 13.8 billion searches in September, down 1 percent from August (which had one additional day compared to September). Google Sites accounted for 9 billion searches, followed by Yahoo! Sites (2.6 billion), Microsoft Sites (1.3 billion), Ask Network (541 million) and AOL LLC (416 million).

(Source:  comScore Report)