According to the BookScan Sales Numbers for 2007, seven manga series sold more than 24,000 copies of each volume on average. Pokemon was one of the seven series that sold 24,000+ on average per volume. Considering no new Pokemon manga's were released in English during 2007, this bodes well for the upcoming Pokemon manga's that were announced earlier this year.
Source:
http://www.animenewsnetwork.com/