Buckle in, folks! It's gonna be a wild ride from here on in.

LinkedIn Corp., the social media network for workers, went public today and its shares, which started out priced at $45, zoomed up to $90.50 in morning trading. It's currently at around $85, as of 10:40 a.m. today. That means, on paper at least, LinkedIn was valued upwards of $8.5 billion.

The Wall Street Journal story this morning noted that investors are hungry for similar IPO stories. By "similar stories," the WSJ probably means everyone is waiting to see how IPOs for Facebook, Twitter, Groupon and Zynga might do.

LinkedIn has been the under-rated, less sexy social media company, compared with those other four. But it was the first one to go IPO. I'd hate to be the last of those companies doing an IPO. Who'll have money to invest at that point?

Seriously though, I have to wonder if how well LinkedIn performs in the next couple of quarters will either whet investors' appetites for more social media companies on Wall Street, or turn them off on such company stocks. It's not a given that a big first day in the stock market for LinkedIn presages successful IPOs for Facebook, Twitter, Groupon and Zynga. LinkedIn, for one, has a lot of work to do for those investors who bought in between $45 and $90 today.

As Michael Moe, chief investment officer of GSV Capital Management in Woodside, California, told Bloomberg News yesterday: “The valuation for LinkedIn is rich. To earn the valuation, it has to continue to grow very, very fast.”

A lot can happen in the next couple of quarters. Internet competitors and the speed in which the market changes is faster than the speed at which Wall Street bankers operate. If LinkedIn knocks it out of the park the next couple quarters, that bodes well for its peers. If not, well, maybe we'll see more IPOs. Or maybe instead we'll see some acquisitions and mergers.