Meebo, the fastest-growing instant-messaging app, allows people to use AOL, Yahoo (YHOO), MSN (MSFT), Google Talk (GOOG), ICQ or Jabber accounts through a Web browser. Meebo claims its users exchange more than 80 million messages a day – and because Meebo uses Web 2.0 technologies that allow people to access messaging networks without downloading special software, it’s more flexible than some competitors. For example, early users of Apple’s (AAPL) iPhone have embraced Meebo as a convenient way to send messages through the Safari Web browser.

The convenient browser-based model has also helped Meebo catch on in Europe and South America, where Internet cafés are popular places to get online.

According to the latest data from market research firm Nielsen//NetRatings, Meebo’s not the only upstart with cause to celebrate. IMVU, which is sort of a Second Life for IM (users take the form of 3D characters as they chat) grew from an estimated 491,000 unique users last August to more than 1.2 million in June. Google’s Google Talk application also saw triple-digit growth.

“Now that instant messaging has become an established form of communication, providers are seeking to distinguish themselves with expanded access and additional functionalities. These recent trends in traffic indicate that users are excited about seeing where the technology is going next,” said Jason Lee, Nielsen//NetRatings media analyst.

*Time Warner is the parent company of the Utility Belt.

The data, below:

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| Site/Application | Aug-06 | Jun-07 | Percent Change |

| | UA (000) | UA (000) | |

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| Meebo | 434 | 1,972 | 354% |

| IMVU | 491 | 1,248 | 154% |

| Google Talk | 904 | 2,252 | 149% |

| paltalk.com | 355* | 447 | 26% |

| Skype (EBAY) | 2,199 | 2,635 | 20% |

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