I say unofficially because all I am doing is opening the Windows Store from the Windows 8 Start Screen, swiping in on the Charms Bar to access the Search Bar and then doing a wildcard search (*.*) to see what comes up in the store.
This morning here is what the results are:
The growth continues at a very good pace and with a little less than a month to general availability on 26 Oct I expect us to see over 3000 apps available.
If you are running Windows 8 RTM you can sort that search by the newest apps added to the Windows Store by clicking on the third drop down box under the results banner.
See any apps that pique your interest?