I just discovered a new one yesterday I hadn't seen before called Apptism:
http://www.apptism.com/ Pretty impressive, too.
Yeah, I just bumped into this one tonight, and was so impressed that I ran back here to post a link. Found yours via the search doohickey. FWIW, this one seems to be the best of the lot, in terms of comprehensiveness, ease of locating and tracking, and timeliness. Good thing too-- the App store's overall sluggishness seems to be going from bad to worst.
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