There's an article on WAG in this week's Barron's. It's mostly a fluff piece with not much new information, but very bullish.
A couple of excerpts:
"Better still, total sales at stores open at least a year, a key retail measure, rose 12%. And same-store sales for front-of-the-store goods, which account for about 35% of revenues, rose 7.5%, the strongest performance in nine years. Deerfield, Ill.-based Walgreen has about 4,300 stores, and controls 13% of the U.S. drug-store market, compared with just 8% some seven years ago."
"Walgreen currently operates stores in 44 states and Puerto Rico, but Rein sees plenty of room for growth, particularly in the nation's southern tier, including parts of California. The company plans to add 400 stores in the near-term, he says, and hopes to have 7,000 stores in 2010. The store base includes about 1,200 24-hour pharmacies, more than the rest of the drug-store industry put together."