I'm picturing a big Venn diagram in my head as I write this. One circle is the mobile Web and the other is the social Web. The overlap seems to be getting bigger by the day with the outer parts of the circles getting smaller. Case in point: Facebook!

Facebook announced some new mobile features this week (for example, one-step sign-in). However, buried in the fine print, the company let it drop that out of the 500 million Facebook users, 200 million are now actively accessing Facebook through mobile devices. Two-hundred million is triple the number from just a year ago.

If you were to graph this, the trajectory of this trend would look like a hockey stick.

Throw in location based services like Facebook's new "Places" feature (its answer to Foursquare) into the mix and you can expect this to be a very long-handled hockey stick.

Case in point, numero dos: Twitter! (Yes, that was an homage to Joe Bob Briggs.)

As recently as September, Twitter published its own stats on mobile users reporting that 16 percent of new sign-ups are starting out on mobile devices. The number of mobile Twitterers is up 62 percent - since April - which boils down to 46 percent of all Twitterers are now active mobile participants. That's 46 percent of the 175 million folks on Twitter to date!

How's that Venn diagram looking to you? What kinds of business opportunities do you see in that quickly growing overlap area?

Whether from your mobile device or otherwise, feel free to follow me on Twitter @oricchio