Jan 3, 2011 16:01 GMT  ·  By

Apple's market cap has just passed the $300 billion milestone, according to early NASDAQ trading listings today.

MacDailyNews is reporting that shares of AAPL are currently up $5.03 (or 1.56%) to $327.59.

This, according to the Apple-centric blog, gives Apple Inc. a market value of $300.50 billion.

The report also includes a list of the top five U.S. publicly-traded companies, based on market value.

In order of market cap valuation, these companies are:

1. Exxon Mobil (XOM) - $374.86B 2. Apple (AAPL) - $300.50B 3. Microsoft (MSFT) - $240.53B 4. Berkshire-Hathaway (BRKA) - $199.05B 5. Wal-Mart (WMT) - $193.67B

Apple has confirmed plans to hold a conference call this month with the purpose of disclosing financial results for the company’s first fiscal quarter for 2011.

“Apple plans to conduct a conference call to discuss financial results of its first fiscal quarter on Tuesday, January 18, 2011 at 2:00 p.m. PT,” the Mac maker announced via its Investor Relations web site last month.

“A link to the conference call webcast will be provided at a later date,” Apple added.

Apple last announced financial results on October 18, 2010, for its fourth quarter ended September 25, 2010.

Q4 saw the company post record revenue of $20.34 billion and net quarterly profit of $4.31 billion, or $4.64 per diluted share.

The results were compared to revenue of $12.21 billion and net quarterly profit of $2.53 billion, or $2.77 per diluted share, recorded in the year-ago quarter.

Gross margin was 36.9 percent compared to 41.8 percent in the year-ago quarter, while international sales accounted for 57 percent of the quarter’s revenue, Apple confirmed in October 2010.

In April 2010, Apple was named Silicon Valley’s most valuable company, having recorded a market capitalization of $224 billion – up 107 percent since the year before.

In May 2010, Apple became the world’s most valuable tech company with Wall Street valuing the Mac maker at $222.12 billion, and Microsoft at $219.18 billion.