That being said, check out http://www.softwareceo.com/attachments/softwareceo/com021908...
Unless you can do something like Google does in not giving out guidance, which seems highly doubtful, the bottom line benchmark seems to be a) a revenue threshold and then b) being able to give decent guidance about future numbers on a quarterly basis. I've always thought the revenue threshold was around 100M, but that link argues it can be smaller for software companies in the right situation.
Few (if any) people on this board have taken a company public.
And your lawyers, and your CFO, and your bank.
I'm inclined to say that if you're asking news.yc whether you're ready to IPO, you're not ready.
I'd be curious to know what it takes to get onto the OTC/BB (pink sheets), b/c those tend to be smaller cap public companies.