Reality checks
Via friendsfriends, a seemingly well-researched financial professional's post showing little to no evidence Six Apart is planning an IPO.
I'd also note from my own experience with the new media industry, the idea that 6A would IPO makes very little sense as well -- they're getting the money they need through VC funding and growth, they're not growing so rapidly that they need more than they can raise independently, and the jackpot in the industry now is getting acquired, not going public (see, e.g., MySpace, YouTube, Blogger, etc.).
I'd also note from my own experience with the new media industry, the idea that 6A would IPO makes very little sense as well -- they're getting the money they need through VC funding and growth, they're not growing so rapidly that they need more than they can raise independently, and the jackpot in the industry now is getting acquired, not going public (see, e.g., MySpace, YouTube, Blogger, etc.).