There was a book published in the late 90s entitled "Barbarians Led By Bill Gates" which was a fairly bitter tale of how backwards one employee (co-author Marlin Eller) felt Microsoft was in the early days.  Unfortunately, the book suffers from all the negativity. 

But one chapter really shines and that is the Chapter on Pen Windows.  Pen Windows was a project attempting to add a Pen interface to Windows 3.1 and it was a project that Mr. Eller worked on directly.  At the time a company named GO was making a lot of noise in tech circles by convincing people that Pen based interfaces were the next big thing.  So Pen Windows was Microsoft's response to that. 

I should mention that, by "Pen interface", we're not talking about drawing on the screen like a tablet but instead about drawing on a Desk pad as a mouse replacement. 

In the end, Pen Windows was a failure and GO went completely out of business.  As a final assessment of the situation Mr. Eller quotes himself as saying this to his partner on the project...

Greg, Look.  This wasn't a thing about making money.  This was all about 'Block that Kick.'  We were on the special team.  We were preventing GO from running away with the market.  That was our job.

Look, your background is in applications, you have to ship the application.  My job is in systems.  Systems, for much longer on, has been completely 'Don't let anybody else steal DOS from us.'  That's all we're doing.  We weren't trying to sell software, we were trying to prevent other people from selling software. 

From my view, Pen Windows was a winner.  We shut down GO.  They spent $75 million pumping up this market, we spent $4 million shooting them down.  They're toast!

I bring this up because news broke yesterday that Facebook will be Open Sourcing their platform in the next week and I think the above quote does a lot to illuminate why. 

The best way for Facebook to eat away at their competition is to keep their competition from innovating.  The easiest way to do that is to hand out the Facebook platform.  That way your competition thinks they're getting the holy grail when in fact they are stunting their own growth.

If a Social Network works exactly like Facebook than there is absolutely no reason for users, developers, et al to leave Facebook.   So while Facebook's competitors probably see the ability to integrate the Facebook platform into their service as a huge opening its actually just Facebook "preventing other people from selling software" 

Plus Facebook gets to kill off Google's OpenSocial in the process.  Not bad for a day's work. 

I think its important to remember that the old rules still apply in the software business.  People might pay for software with their eyes rather than their wallets but they are still paying for software and companies still need to compete for that currency.  I might not like tactics like this one but they show Facebook is paying attention to the past and in my book that puts them ahead of the competition.