I would like to be able to retrieve key/value pairs of metadata for stored objects. I'm going to look into adding support for this.

I went to go implement this in the code and realized support was already there for doing a HEAD request if you create the GetObjectRequest object yourself. Slightly messy since you have to do the try/catch block and WebException handling in user code, but it works. Not sure how to close this issue, sorry about that.

Yes I think the core problem is that the "underlying" objects such as GetObjectRequest are not very discoverable right now.

But there is definitely support for getting object metadata like you found out, and there's an example for it on the Examples page in the Wiki.