Suddenly it feels like 1999.

LinkedIn reportedly is planning to go public this year.It likely wont be alone among the shiny, new social media start-ups. Twitter, Groupon and Zynga could well joinLinkedIn in tapping the public markets this year. That list ignores Facebook, which wont go public this year but likely will in 2012.

Yet all the noise of social media IPOs, obscures the fact the market was already heading toward a much improve 2011.

One week into the year, 110 companies have filed to go public. (Filling is not the same as going public, of course.) The estimated value of these IPOs? $21 billion and change. At the same time last year, there were 61 deals in the pipeline valued at $11 billion, according to Dealogic.

In all, 110 U.S. companies went public last year valued $35 billion, according to Dealogic. And that figured was skewed by GM which accounted for nearly half the volume. Still the number of U.S. companies that went public last year was double what was seen in 2009.