Count Om Malik among those who were surprised that Twitter had a profitable year in 2009.  Not that he isn't optimistic about the social media wunderkind's current and future value--in fact, he thinks Twitter isn't charging Google and Microsoft (the companies that accounted for Twitter's revenue this year).  It's just that he didn't expect the company to be in the black by now.  But he does expect Twitter to start spending in three key areas next year:

*New management team including several new “C”-suite executives.
*Infrastructure to scale their network to accommodate future growth.
*Hiring more engineers and other key people as it tries to build out the service.
Which means the so-called profits are going to evaporate and the company will have to dip into its $155 million (VC) cash hoard. Even the soon-to-come commercial accounts might not be enough to make up for all that spending.

Read Twitter May Be Profitable — No, Seriously! here.