Apple is now the third largest company in America by market cap, having overtaken Wal-Mart for the number three position.  At $236.86 the market cap of Apple is roughly US$214.75 billion, compared to Wal-Mart at $55.95 with a $212.9 billion market cap, according to "24/7 Wall Street" (http://247wallst.com/2010/03/30/value-shock-apple-larger-than-wal-mart-m...).
On an enterprise value including debt, Wal-Mart still maintains the lead over Apple as it has over $36 billion in long-term debt versus only about $5 billion for Apple, and Apple’s longer-term liabilities are not even real debt issuance, the article adds. Our favorite tech company will probably never reach the top spot when it comes to US market cap status in the U.S. as ExxonMobil's market cap is $317 billion -- and that's with shares closer to a 52-week low rather than an all-time high. 
Still, "24/7 Wall Street" says "there is one challenge and one that the Apple lovers would absolutely love." Microsoft sits with a market cap just shy of $260 billion. Apple “only” has to rally about 21% and Microsoft has to stay static "for there to be a real war of the market caps on top of a real war for the consumer electronics and computer spending," says "24/7 Wall Street."
