Catching up on my aggregator yesterday I saw that Dare had posted about Sun's response to Silverlight: their own rich internet application (RIA) framework to supplant (though the politically correct answer is not that it would, it's just a "new opportunity") some of the Web 2.0/AJAXish things that have been popular of late. Mary Joe Foley presents a noncommittal analysis and Sam Ruby points to a few resources.
I went to Sun's page and although it seems like a real enough project the fact that it's applet based right now (and far slower than the Silverlight beta in installing) seems to point to it as an unfinished thought. Their demos at this point are not just slow, but rather underwhelming - compare that with the MLB demo at Silverlight and it's quite a contrast.
But I'm willing to assume that Sun is serious and that their technology has a lot of appeal, especially to many people who live on the "Not Microsoft" koolaid. If that's the case there is a three way battle going on between Adobe, Sun, and Microsoft for how RIAs will be developed.
I wonder if it's wise in a situation like this to hope for a clear winner; competition should hopefully produce the best technology out of each company. Although there will doubtless be compatibility questions that come up, but because each seems to be plugin/runtime based, it seems like developers will have an opportunity to choose a target and build with/for it rather than some of the monkeying around that needs to be done to make a web application work on multiple browsers.