I'm working on a project where we're planning on using 'events' to notify different users REAL TIME of changes in entities they have expressed an interest in. Currently we have focussed on JMS to manage these 'events' but I've been looking into Jabber this weekend, thinking it might have possibilities.
Has anyone ever compared these two technologies - advantages vs. disadvantages? Anyone had experience in development using Jabber in an Enterprise application?
I don't know Jabber, but Jabber and JMS seem to offer different qualities of service, so it depends what you need. JMS will give you assured delivery (i.e. guaranteed "once and only once") with persistent delivery mode, or "at most once" with non-persistent (yeah, I know about DUPS_OK, but I don't want to complicate it!). It can even be transactional, although it doesn't sound like you need it. You can use durable subscribers to store messages for clients even when they are offline (or if they crash and restart).
As far as I can tell from the website Jabber seems to have no quality of service guarantee, so you're not sure if your message will arrive or not. The client will also need to be online to receive. These may or may not be a problem for you.
Apart from that there's the usual JMS 'advantages' - J2EE (easy to publish to an MDB, for example), standards, provider-independence etc...