Tips about an Apple store along Walnut Street in downtown Philadelphia (Penn.) first surfaced in 2004. But perhaps like the company’s real estate team, the tipsters could never pinpoint an exact location until mid-2009. Now one of the longest-running store projects is over, and the Walnut Street store will open this Friday at 5 p.m. Located about 10 blocks from historic Independence Hall, the new store at 1607 Walnut Street will fill in coverage previously provided by suburban Pennsylvania and New Jersey stores. The store features an impressive, two-level stone façade, but standard interior design features.