Micro-blogging site Twitter is interested in making more acquisitions as it continues to grow in popularity, co-founder Biz Stone said on Tuesday.

That is something we are definitely interested in, Stone told a news conference in Tel Aviv. We made an acquisition last year that turned out to be an outstandingly good decision.

He said there was nothing specific on the horizon.

As our attention is grabbed by some of these developers, we will take a hard look at them, Stone said.

Twitter bought search engine Summize in 2008.

Stone said Twitter will start making money in 2010 as it unveils a plan early next year on how it will produce revenue through advertising. He declined to give details but said advertising will be non-traditional.

There are no dates when we need to break even. We have plenty of money in the bank, he said.

In September, Twitter received a new round of funding from investors including mutual fund giant T. Rowe Price and private equity firm Insight Venture Partners, which analysts said set the stage for an eventual initial public offering or sale.

According to a person familiar with the matter, the new funds totaled $100 million, theoretically valuing the company at $1 billion.

Stone on Monday said Twitter may eventually go to the stock market for funding if necessary.

Twitter, which lets people send, or tweet, 140-character text messages to groups of followers, is one of the world's fastest-growing social Internet companies.

Worldwide visitors to its site hit 44.5 million in June, up 15-fold from a year earlier, according to tracker comScore.

Twitter last month forged deals with Microsoft and Google to allow access for its real-time content. It also linked up with professional social network site LinkedIn earlier in November.

Stone said Twitter was looking to partner with as many websites as possible and that Twitter would keep its platform open for developers.

Stone noted that for now, Twitter will be in English with a next wave into French, German, Italian and Spanish.

If that works out well, you will see more languages, he said.

(Editing by David Cowell)

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