The current count of known exoplanets is now 497. It is being estimated that the number could reach or pass 500 by January. Kepler alone has already found an additional 750+ candidates, just from its first 43 days of operation. These statements from that article, by astronomer Geoffrey Marcy and planetary scientist Sara Seager, sum it up nicely:
“Many of the candidates Kepler discovered are now getting verified with radial velocity confirmations. “On Feb. 1, we’ll announce all of them — a huge avalanche of exoplanet candidates,” Marcy said.”
“The days of having to have perfect exoplanets are going away,” Seager noted. “We’re going to publish so many planets that we’re not going to be able to validate all of them. Instead, we’ll have so many we can start studying them statistically in groups.”
See also this previous article.