What is JPEG XR? It's HD Photo, from Microsoft, now on its third renaming. Likely this standardization process will put all patent worries to rest.
I don't see much mention recently of T.851, the simple improvement to JPEG, with better lossless compression than Huffman, and 16-bit support.
Things I like about HDP/JPEG-XR: high bit-depth support, streaming all the way to lossless, fast decompression. Things I don't: quality.
Sachin Garg has done a reasonably good study of this, and at typical bitrates (say, 0.5-1.5bpp), JPEG actually beats HDP/JPEG-XR: http://www.imagecompression.info/lossy/ and it would do even better with T.851.