It has been clear for weeks that the micro-messaging service Twitter was close to raising a new round of capital as interest around the site (and arguably the site itself) explodes. Tonight GigaOM’s Om Malik reports that the site has not finalized a $15-20 million round as was previously rumored, but instead is in the middle of a bidding war between at least a couple VC funds.

According to Malik, these rounds will put Twitter’s valuation north of $70 million, but presumably still beneath the $150 million ceiling we discussed last month. But who knows, anything is possible when you have a bidding war.

Perhaps now we know why Twitter hasn’t used some of its millions to secure some talent to fix its issues — it hasn’t secured the money yet. When it does, will all of the downtime issues be resolved? Let’s hope so.

Twitter raised $5 million last year from Union Square Ventures and Charles River Ventures.

We have some feelers out on this development and will update when we hear back.