The rapidly expanding Windows Phone 7 Marketplace (MFST -0.2%) mobile apps store now sells over...

|By:, SA News Editor

The rapidly expanding Windows Phone 7 Marketplace (MFST -0.2%) mobile apps store now sells over 4K apps, up from 3K on Nov. 25. App variety is key to driving market acceptance, so this is at least a sign that Windows Phone 7 may yet get a foothold against Apple (AAPL) and Google (GOOG).