As we sit and wait for the Facebook IPO to actually happen, some investors are beginning to question the value of investing in Facebook, and more specifically, if there will be enough growth to make their investments worth while.

If you remember, the IPO is hoping to raise $5 billion. Just a couple weeks ago, estimates were reporting a $104 billion valuation of Facebook, and that is what private trading of the stock has reflected. As of last month, Private trading of the stock has ceased as CEO Mark Zuckerberg and Facebook prepare for the forthcoming IPO, and some experts have come out to say the valuation of the company may be too high.

Business Insider is reporting on estimates from Capstone analyst, Rory Maher, and they say, $90 billion is a closer estimate for the true valuation of Facebook. Here are the reasons he gives for the lower estimate: a lower revenue growth year-over-year, and quarter-over-quarter, less than expected traction from premium ads, and lower EBITDA margins than what were originally expected.

There is no word from Facebook or CEO Mark Zuckerberg on these decreased estimates, but we can look forward to the IPO in the next month or so and investors can make their decisions then as to the risk of their investment. To be sure, we’ll have to wait and see what returns those investments bring shareholders. I still believe it will be a hot stock as soon as it becomes available on the NASDAQ. We’ll keep you up to date on all the developments with the value of Facebook and any IPO happening.