I know it sounds bizarre, but I do have a theory to substantiate this. Don't know how to formulate it so just listing it.
1. Google is a closed source company. Ok, to begin with, Google internally uses Linux ( all that hype about Gooobuntu ), contributes to MySQL and supports Mozilla foundation. However, how many of Google own software are open source ?? Zilch!! Zero. Its like Google loves to take advantage of open source technologies, for its own benefit, but refuses to make its own products open source. Even its Linux products, like Linux Desktop Search and Picassa, are closed source. In todays world, Google and M$ are two biggest technology companies for desktop users. As they both promote closed source, are they not helping promote the notion that closed source is not evil -- one of the biggest motivating factor for people using Linux.
2. Most, if not all, of Google's applications are on Windows. Google has just started porting its existing applications to Linux, the first being desktop search. Picassa for Linux is just a "wine" adaptation of windows version of Picassa.
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