I'm pretty sure they've done that just using a combination of HTML/CSS and Javascript... So it's not really an "off-the-shelf" product as such, you'd have to write some code to get the results you want (but that's also it's strength - you can customize it to be just what you're looking for)... Still I think with some digging around (I'll take a look tomorrow, about to hit the hay!!) you could probably find the source-code for a basic slideshow page which would be a good starting point, and build in the RSS and stuff from there... Sound okay?
Edit: I couldn't resist doing a little digging... here's the article where I found that example:
http://designshack.net/articles/jav...-photography-slideshow-website-without-flash/
It is actually a tutorial which would act as a reasonable starting point to get to where you want (though as it's got slightly different aims in mind it will probably require a bit of tweaking to your needs)... Skimming it it looks as though they are using Jquery (Javascript basically)... He starts from a pre-made (and free) plugin for Jquery which gives a sort of slideshow effect and then customises it by removing the slideshow controls etc. to get the final result... So yeah - have a read and you should get an idea at least of what's involved... And of course note that this is only one of
several possible approaches (which would be similar but not exactly the same) - this is pretty much the first result I found on Google which sounded along the right lines