I was doing mine to enable two microblogging servers to talk to the world and wanted to abstract the posting mechanism from the microblogging server so I had given some thought to the amount of information contained within the ping. Using a fat ping to ensure that the data is all contained in the message means that you will not get a potential swamping of the sever when the subscibers rush to get the update but what update to provide? For me it comes down to the fact that as a protocol it is very flexible and does not require this decision to be made to use it. Accordingly I would see it as each as to its merits.

Certainly for my purposes it was more a case of the entire message with “attachments” files, photos etc not having to be present but just the relevant links being in the message which was accordingly very small.

It may be that there are further standards or protocols that emerge that use PuSH as the carrier but I do think that with ease of use and deployment this is the type of thing that will be central to the way the web is used in the not too distant future.