[Correction: This article originally overlooked the existence of the Vanguard FTSE All-World ex-U.S. ETF (AMEX: VEU)]

Vanguard has added a fully global ETF to its line-up of funds: On Thursday, the index fund provider launched the Vanguard Total World Stock Index Fund, which comes in Investor, Institutional and-of course-ETF shares.

There aren't a lot of truly "global" ETFs out there-ones that offer broad coverage both of developed and emerging markets. Barclays Global Investors and State Street Global Advisors offer such funds, and interestingly enough, all three of those funds track indexes from MSCI. There are two "ex-U.S." ETFs-the SPDR MSCI ACWI ex-U.S. ETF (AMEX: CWI) and the iShares MSCI ACWI ex-U.S. Index Fund (NASDAQ: ACWX)-and one completely global ETF, the iShares MSCI ACWI (NASDAQ: ACWI).

Besides this latest product launch, Vanguard also has the Vanguard FTSE All-World ex-U.S. ETF (AMEX: VEU), which tracks almost the same index as the new ETF does, except without the inclusion of the United States. So that makes four global funds, two of which track the same exact index.

The new Vanguard fund tracks the FTSE All-World Index, which weights the United States at about 41%, and the rest of the world-both developed and emerging markets-at 59% of the index. In all, the index covers about 2,900 large- and mid-cap stocks domiciled in 47 different countries.

"We view the new offering as an ideal ‘foundation fund' for a well-diversified investment portfolio," said Gus Sauter, Vanguard's chief investment officer.

The ETF shares, which trade on the NYSE Arca exchange under the symbol VT, charge an expense ratio of 0.25% (as does VEU), making them cheaper than CWI, ACWI and ACWX, which all charge 0.35%. VT's lower price could overcome the first-mover advantage held by the other funds. CWI-the first to launch of the three-has about $329 million in assets, while ACWI and ACWX have about $69 million and $20 million in assets, respectively.

At least one other global ETF is in registration: The NETS Dow Jones Wilshire Global Total Market Index Fund from Northern Trust could probably hit the market at any time. The broad index covers 58 countries and more than 12,800 companies.

Meanwhile, the Institutional and Investor shares of the new global Vanguard fund charge expense ratios of 0.20% and 0.45%, respectively. However, the Institutional and Investor shares also carry a 0.25% purchase fee because of the added transaction costs associated with international investments, and charge a 2% early-redemption fee for the redemption of shares after less than two months of ownership. Given that Vanguard also recently announced the reduction or elimination of purchase fees for two of its existing funds, these fees may also disappear once the fund acquires enough assets.