Should I stick to the Open Source, or its time to explore the .net world
I have been developing professionally websites/applications for almost 5 years, using PHP (Zend Framework) with Oracle/MySQL.
Currently I am getting deeply into distributed system design, and SOA.

I intend to learn new powerful language like JAVA, and a framework like SPRING, to widen my horizons, and increase my career growth possibilities.

**But I am confused in a way. Question is: why I would learn a new open source language.. I know 
already know one which is PHP, and I deal with open source systems like Linux.
Should I learn another open source language, or its time to explore the .NET world?
which path I should take? being totally into open source languages, or having mixed background?
which path will extremely benefit me on the long term?**

I just intend to learn only one language besides PHP, so I have enough time to know its ins/outs/frameworks/quirks, and to master it.. I don't have enough time to explore/use every single language around.
so my decision now is considered strategic and it will affect me on the long term big time.

I am not asking to know which is a better language,or which language is more powerful,  yet I am asking to know what path yields the best results, and benefits me the most.

Reasons to which path I should take, also Pros and Cons are highly appreciated.

Thanks in advance.
Should I stick to the Open Source, or its time to explore the .net world
===

I have been developing professionally websites/applications for almost 5 years, using PHP (Zend Framework) with Oracle/MySQL.
Currently I am getting deeply into distributed system design, and SOA.

I intend to learn new powerful language like JAVA, and a framework like SPRING, to widen my horizons, and increase my career growth possibilities.

**But I am confused in a way. Question is: why I would learn a new open source language.. I know 
already know one which is PHP, and I deal with open source systems like Linux.
Should I learn another open source language, or its time to explore the .NET world?
which path I should take? being totally into open source languages, or having mixed background?
which path will extremely benefit me on the long term?**

I just intend to learn only one language besides PHP, so I have enough time to know its ins/outs/frameworks/quirks, and to master it.. I don't have enough time to explore/use every single language around.
so my decision now is considered strategic and it will affect me on the long term big time.

I am not asking to know which is a better language,or which language is more powerful,  yet I am asking to know what path yields the best results, and benefits me the most.

Reasons to which path I should take, also Pros and Cons are highly appreciated.

Thanks in advance.