Twitter is about to raise a boatload of cash. Last week we broke the news that Twitter is raising another round of funding at a $1 billion valuation and that one of the new investors in that round is Insight Venture Partners. Initially, Twitter was trying to raise $50 million, but demand for its shares is so great that it is raising even more.

The WSJ is reporting that the round may close as early as later today, and that Twitter may end up raising close to $100 million. In addition to Insight Venture Partners, another new investor is T. Rowe Price. In February, 2009, Twitter raised $35 million at a $250 million valuation.

Raising that much cash at a $1 billion valuation should hold it over until it decides to go public or is bought for a ridiculously large sum. (The price to acquire it just went way up). It also will put Twitter in the major leagues, and give it the resources to keep scaling its service. No more excuses for outages or technical hiccups.

More details as they come in.