The changes look good , infact very good. it is highly optimized.
You already incorporated the Document changes which i added
The writeUTF bug was a very critical one which I noticed after cutting the patch.Anyway you fixed it.
I guess one test is failing in TestDistributedSearch
need to take a look
I vote vote for preserving SimpleOrderedMap.(anyway there is are two reserved types one can be taken up)
Makee sense to use this in SolrJ . But there are people using SolrJ with Solr1.2 and older versions of Solr1.3 in production. We must take care of that in the code.
read the response header, if the content type is application/octet-steram use BinaryResponseParser or use XMLResponseparser