Recently Palm announced the release of its new Palm WebOS 2.0 software development kit — I know, be still my beating heart — but it matters, because it gives developers new tools that let their apps do some very cool things.

For instance, there’s a new feature called “Stacks.” Palm now opens windows in the form of cards. Hit browser, a card appears. Keeping with the card theme, related windows will open in a “stack” that looks like a hand of cards that are fanned out. So if someone sends you an e-mail with a link to a Web page, and you open that page from the link, both the e-mail and the Web page will appear in a stack. The idea is to link windows by task, rather than by the application that runs them.

The new system will also refine Universal Search, which let users just start typing and have the phone find matches whether it was in the contacts or elsewhere. But the original version only worked for a few apps. The new system lets more apps in on the fun, so you might buy a dictionary app and when you started typing it would be included in the search with contacts and the rest. They have renamed the feature “Just Type,” which also connects with a open-source search system that will let you probe lots of sites, including CNN, from your home screen. You’ll also be able to initiate text or e-mails without having to go and start their respective apps.

Then there is a new feature called “exhibition.” Currently when you put your Palm on the magnetic charging dock a clock shows on the display. By giving developers access to this feature, they will be able to create all kinds of new displays (say, a stock ticker, a radio station, a weather report or video) that automatically comes on when your phone is charging.

A lot of the improvements are kind of geeky and will be more behind-the-curtain, like one that will let apps run more services in the background from the Web. The company says they are also improving the graphic tools so that games can be ported more easily from other sources.

And of course, as with any new operating system, Palm promises it will be better, faster, easier.

Palm is also promising new “form factors.” That means it will bring Web OS to many computers, slate computers and, it says, printers (thanks in part to Palm being purchased by HP), so that its apps can run lots of stuff from your phone.

All in all, some good and real improvements, but will it be enough? In a world defined by BlackberryOS, iOS and Android (not to mention a forthcoming salvo from Microsoft), is there room for five mobile platforms? Can Palm, with access to HP’s deep pockets, be one of the success stories?