I hadn’t a clue anyone was working on implementing features of HTML 5 but the WebKit team just announced Javascript client side database support. Check out how easy this code looks:

database.executeSql("SELECT * FROM test", function(result1) {
   // do something with the results
   database.executeSql("DROP TABLE test", function(result2) {
     // do some more stuff
     alert("My second database query finished executing!");
   });
});

If you have the webkit nightly installed visit this sample page to view it in action. It also comes with a kickass Inspector that shows contents of databases/tables right there from safari.

I think this is potentially bigger news for MobileSafari on the iPhone. My reasoning is this: When developing web apps, you must support all browsers, mainly IE 6+7, Firefox 2+, and Safari 2+. If WebKit is the only browser that has this Client Side DB library, no developers will be able to use it for any serious application (by serious I mean for a business aka something people make money on). But they WILL be able to use this Client Side DB for MobileSafari apps, since its a closed platform and a lot of people are developing webapps specfically for use on the iPhone. This gives the web app developers hope that they haven’t become completely second class citizens.