If you ask any technology marketing person, they'll tell you that the only thing important about getting people to look at your technology is buzzwords. They're wrong. But buzzwords are useful. They're a decent way to get a quick sense of what someone thinks is cool about a technology in a jargon that everyone (mostly) understands. They're the design patterns of the marketing world, if you will.
Some of the things that make Jifty rock
DRY (Don't Repeat Yourself)
Jifty tries not to make you say things more than once. And in a lot of cases, Jifty tries not to even make you say them at all, unless you want to.
Out of the proverbial box, Jifty comes with one way to do everything you should need to do: one database mapper, one templating system, one web services layer, one AJAX toolkit, one set of handlers for standalone or FastCGI servers. We work hard to make all the bits play well together, so you don't have to.
With Jifty, it's easy to let the user go off and do something else -- fill out a wizard, look something up in the help system, or go twiddle their preferences -- and come right back to where they were.
This is one of the things that Jifty does that we've not seen anywhere else. Jifty owns your form rendering and processing. This means you never need to write form handling logic. All you say is "I want an input for this argument here," and Jifty takes care of the rest. (Even auto-completion and validation!)
Jifty is written in Perl. If you're familiar with Ruby, Perl might feel like Ruby's quirky big brother. ;)
If it's out there, it's in CPAN. Everything from AtomAPI libraries to Z39.50 library gateways.
Jifty is the only web application framework that comes with a pony.