Unless you've got a specific feature you need, I would look at best being:
a) Whatever platform you are developing the program in -- there are lots of advantages to not having to switch tools/contexts/platforms to muck around with the search internals.
b) Whatever platform your ops guys want to deal with -- I know lots of windows ops guys hate dealing with java as it is a strange foreign language. For example.
c) All of the above being equal, Java is the real flagship lucene project that everyone else is keeping up with with and that has the most tools & resources. It is the way to go if you don't have any reason not to use java. Solr is another advantage here -- you can pretty easily use a pre-wrapped fully functional lucene http server.
In any case, keep in mind that at least theoretically any lucene index written on one platform is readable by others so you don't necessarily have to fully commit to a single platform.