I’d been hearing whispers as of late that Twilio is meeting with VCs to raise another round, and I just got the good word from a very, very solid source.

I’m told that Twilio is in the process of raising a Series D, with a goal of raising around $50 million.

The talks are still rather early on. In fact, when I first got wind of the round last week, the first folks I asked were shocked that we’d already heard about it. At this point, it sounds like Twilio is aiming to close the round within the next 2 to 3 weeks. The total amount raised might change by then, but $50M is the current target.

Wondering what the heck a Twilio is? Twilio lets developers easily build things that require phone functionality. Want to build a customer service line with menus narrated by Morgan Freeman? Sure (note: bring your own Morgan Freeman. Also, someone please do this. I’ll totally write about it.) Want to build a tool that’ll text you the second Netflix’s Arrested Development revival season goes live? Already done. If you need to programmatically do something that goes down over the phone — be it SMS, voice calls, or VoIP — Twilio can probably do most of the leg work with just a few lines of code.

Twilio is actually one of my favorite companies in the valley right now, for at least two reasons: they make a damned cool product that in turn enables other damned cool products to be made, and very few people seem to realize how well they’re doing. While their CEO Jeff Lawson seems to prefer keeping their financials hush, every whisper I hear about the company suggests that they’re quietly kicking ass.

Amongst other good signs: the company is hiring like mad, to the point that they just (as in, this week) had to move into a much bigger office. They actually couldn’t find a ready-to-go office in SOMA with enough space for their growing team, so they spent the better part of the last year retrofitting a spot on Harrison Street that once served as a paper/textile factory.

Twilio has raised $33.5M to date, having most recently closed a $17M Series C at the end of 2011. If they successfully raise $50M, it’d be an injection roughly 1.5x larger than everything they’ve raised so far.

When I first started digging around this story, no one I spoke to could seem to agree on which VC firms were involved. Turns out, Twilio is just talking to a lot of firms. Two names that seem quite certain to be in talks at this point are Union Square Ventures and Bessemer Venture Partners — which makes sense, as USV has been re-upping with Twilio since their Series A, and Bessemer has supported them since their Series B.

Keep an eye on these guys, if you’re not already. If things keep going as they are, I’d bet on them going public within the next year.

Excerpt from: Twilio Is Raising A Series D Of Around $50M