Groupon’s plan to go public appears to be moving forward yet again.  Although nothing’s been confirmed through official channels, new reports indicate the company’s picked Goldman Sachs and Morgan Stanley to underwrite its IPO, and there are new rumors about the timing and size of the offering, too.

Anupreeta Das and Gina Chon spoke to anonymous “people familiar with the matter,” and afterwards reported, “The IPO is expected to value the Chicago company at between $15 billion and $20 billion, these people said. . . .  Groupon hasn’t decided exactly how much it plans to raise from the initial offering of its stock to investors, but it could be as much as $1 billion, according to the people . . .”

Then the pair continued, “The IPO is currently planned for the second-half of 2011, and will potentially be in the third quarter, one of these people said.”

That all roughly matches up with other rumors that have circulated in recent weeks.  Clare Baldwin heard some of the same details from an anonymous source (though possibly the same one), as well.

It should be interesting to see if Groupon pulls this off.  Google’s own IPO only valued it at around $23 billion, meaning Groupon would arguably be asking a lot of investors.

Also, there’s no telling what the stock market will look like by the time Groupon moves forward, so if inflation and oil prices continue to rise, a social media company that’s in Google’s sights might not seem to be the safest bet.