We know it's a challenge for start-ups to go public in a recession–potential investors have less money and there is a shortage of risk tolerance. We know recessions create a particularly rough environment for restaurants–people choose to eat out less and they book fewer tables. What we don't know, is how OpenTable, a formerly venture-backed online-reservation booker, managed to achieve a 59 percent increase from its initial public offering of $20 by the close of day, when it went to Wall Street the last week in May.

OpenTable's success follows closely in the wake of that of another formerly venture-backed start-up, SolarWinds, a network-management software company that went public on May 20 and saw its IPO grow 10 percent from $12.50.

While some industry analysts say the market might be growing for IPOs, Scott Sweet, senior managing partner of advisory firm IPOBoutique.com, believes there has been some positive movement, but that OpenTable was an exception.

"OpenTable is incredibly over-valued," he says. "OpenTable really did well because it was such a small offering–three million shares."

The past decade shows a steep downward trend. In 1999, there were a record-setting 486 IPOs. Last year, there were 43. The recent offerings of two-time Inc. 5000 honoree SolarWinds and OpenTable bring this year's tally to seven.

Even though the market is too scared for IPOs to succeed on a large scale according to Sweet, there are criteria that will help individual companies get where they need to be.

"Right now, to be a good IPO candidate, you need increasing revenues, increasing profits, and low debt," Sweet says. "Without it, you better have an incredible concept."