The output of Azaroth’s meeting with A9 is up on their blog. Sounds like it will be a meeting of the minds, halfway type of thing. Being extension’s it might make it possible to keep the great simplicity of OpenSearch while taking advantage of some of the more advanced queries that SRU allows. From the post:

Will be interesting to see where this leads. I was playing around with allowing CQL type queries in opensearch but this will make it much more standardized.