When Microsoft launched Windows Mobile 6.5 earlier this month, the latest version of the company's operating system for cellphones and mobile devices was met with lukewarm (if not hostile) reviews. In a nutshell, the biggest complaint is that the operating system was essentially unchanged from the previous few versions and didn't offer much to convince users to stick with the platform instead of switching to an iPhone, Blackberry, Google Android, or Palm device.

But there may be hope. Windows Mobile 6.5 does have a new and improved web browser and home screen, even if the calendar and contacts applications haven't changed in half a decade. And now it looks like Microsoft is working on an incremental update that may or may not be called Windows Mobile 6.5.1 that will bring a number of minor but significant improvements.

Unofficial builds of Windows Mobile 6.5 have been leaking onto the web for the past few months, and blogger Long Zheng reports that among other things:

• There's a new contact application that's more finger-friendly
• The start menu and close buttons have been moved to the bottom toolbar, which allows the toolbar at the top to be thinner and hold status icons only
• UI elements including buttons and check boxes have received a visual refresh

Windows Mobile 7 is expected out next year, and it will reportedly represent a major shift by including more finger-friendly controls and a new version of Office Mobile. But until then, it sounds like Windows Mobile 6.5.1 might be the way to go if you're stuck with a Windows Mobile device. Long Zheng reports that early builds are already available for download for some mobile phones in the shadier areas of the internet.