I remember reading one of the Mark Little's posts (sorry can't find the link) where he was saying that, yes, it was possible to write transactions in REST, in fact he'd even had some practical experience in that area before.
Yes, while I don't have such experience I know now how I can do it now with REST.
Then Mark said that a number of partners had managed to demonstrate the interoperability of one of WS-* Transaction specification as part of some of the interoperability events.
This makes me wonder : is it what actually defines Web Services ? Not only the actual technology per se but the fact that multiple businesses can do the same technology and successfully interoperate ?
Will it ever happen with RESTful services ? Will it be possible for multiple companies to interoperate with more sophisticated things involved such as transactions, for ex, something which is possible to do with WS-BusinessActivity which does not really lock all involved ?
Or is it something which will not be ever needed in practice ? Local transactions, different business alliance-specific standards is all what will be needed to either just do transactions or achieve the interoperability in say the transactions area ?