On Jan 21, 2013, at 8:04 PM, David Fiander <[log in to unmask]> wrote:
> The documentation for the APIs is weak, and it looks like it hasn't been
> updated for a while. Has anybody used them much, or know what the state of
> ongoing development of them is?

I am pretty sure that there is no ongoing development of Open Library.  Others may be able to provide more details.
> 
> All I'm really looking for at this point is a way to convert an ISBN into
> basic bibliographic data, and to find any related ISBNs, a la OCLC's xISBN
> service.

You can't do this via the API, because there's no way to search for work_id (at least none that I'm aware of).  I was running an xISBN clone with the OL data, but it stopped working when Talis shut down the Platform...

The dataset isn't that large, however.  It may be worthwhile to download it and create your own xisbn style services.  It might be even better to hack up something at Code4lib13 (or, elsewhere) to take the monthly dumps and create a similar service.  I imagine you're not alone in wanting this.

-Ross.