Recently I've been getting more and more into mobile development. I am currently working with the iPhone and Android based devices.
Palm's new WebOS looks interesting.
Are there any good online tutorials for quickly getting up to speed on developing for the Palm WebOS?
The Palm Developer Network has some basic overviews: http://developer.palm.com/
They also have a section up there: Palm webOS: Developing Applications in JavaScript Using the Palm Mojo Framework. This may be a good start.
Palm webOS: Developing Applications in JavaScript Using the Palm Mojo Framework is a book in the making, available currently through O'Reilly Rough Cuts program).
You can easily read the first chapter.
That's the closest you can get currently from official sources. Unless you apply to their SDK early access program (sdkapplication.palm.com/sdkapplication) and they let you in (you can apply for it until the SDK is officially released to the public).
Of course, another thing we can do until the SDK is out is catch up on whatever technologies we individually need that programming for Palm's webOS will require: JavaScript, HTML5, CSS... and there's ton of material about these online. Actually, there are many websites dedicated to Palm Pre and webOS that sprung up recently. The one that is more programming oriented that I know of is webOShelp.net: take a look at their Getting started with webOS guide (www.weboshelp.net/getting-started-with-webos).
P.S. sorry about not clickable links, had to play the system somehow ;) - it won't allow me to post more than one link since I'm new here.
Now that the device is out, people are actively playing with the device. Best site I have found so far is (no affiliation) http://predev.wikidot.com
Also, if you root the device, you can look at the source for the shipped apps in /usr/palm/applications
I have additional notes at http://ff.im/44nCw
This blog has a good tutorials: http://kmdarshan.com/wordpress/?p=3305