Shares of Apple (NYSE: AAPL) spent most of Wednesday above the $500 billion market capitalization mark as they also sit a new record of $547.61.

The shares closed at $542.44, up $7.03, bringing the company's market value to $505.5 billion. On Tuesday, the company's market capitalization at the close was $499.2 billion.

The valuation sustains the Cupertino, Calif.-based electronics, computing, smartphone and entertainment provider as the world's most valuable company.

Shares of No. 2, ExxonMobil, the No. 1 U.S. energy company, fell 64 cents to $86.50, valuing the Houston-based company at $407.7 billion. Apple and ExxonMobil have been neck-in-neck at times since August.

While overall U.S. markets fell slightly, Apple shares gained momentum from their cult-like following as investors anticipate new profits from sales of the long-awaited iPad 3  tablet scheduled to be introduced next Wednesday.

Apple has sold about 55 million copies of the iPad and iPad 2, so a refreshment has long been anticipated. Apple's Asian manufacturers, mainly Taiwan's Hon Hai Precision Industries, have been working to build inventory for the new products.

Shares of Hon Hai, also known as Foxconn, rose 3.5 percent in Taipei. They are up nearly 24 percent in 2012.

Apple shares are already up 34 percent this year and 55 percent over the past 52 weeks.

Being No. 1 in value in technology can be transitory. Microsoft, Intel and Cisco Systems were all the world's most valuable companies at one point before losing the crown. Microsoft is now valued around $266 billion, Intel at $135 billion and Cisco at $107 billion.