They have been a long time coming, but handsets running the Windows Phone 7 operating system – probably Microsoft’s last roll of the dice in the smartphone market – are finally ready to take on the iPhones, the Droids, the Blackberries and the Galaxies. What’s more, these outriders are being escorted to the top table by the big guns in the mobile operator community.

In what looks like a strategic play to make Microsoft a stronger counterweight to Apple, RIM and Google, America Movil, AT&T, O2, Orange, T-Mobile, Verizon and Vodafone are among the 60 mobile operators who have said they will offer Windows 7 handsets to their customers, ensuring these new devices will be marketed to tens of millions of people around the world. Ironically, mobile operators, who have long complained about too much fragmentation in the smartphone platform market, now seem to be encouraging diversity.

To be sure, operators’ support for Windows Phone 7 isn’t all motivated by fear of Silicon Valley. Windows-based smartphones will have a certain appeal to corporate IT managers looking for handsets that work well with their existing inventory of laptops and servers running Microsoft’s software. Moreover, early reviews suggest that Windows Phone 7 is a marked improvement over its lacklustre predecessors, while also sporting some innovative features, such as the Live Tiles on the home-screen, which pull down real-time news and status updates from the web.

For the fashionable?

But a big fan base in the operator community won’t be enough to ensure the success of Windows Phone 7. Despite its longstanding and loyal following in the developer community, Microsoft will have to work hard to convince mobile specialists to code for its platform ahead of iOS, Android, BlackBerry OS and Symbian. Developers loathe fragmentation more than mobile operators because it dramatically increases their costs.

Then there is the question of how much support Windows Phone 7 will get from handset manufacturers. Samsung, LG, HTC and Dell have all unveiled new models running Windows 7, but most of this group probably still regard Android as a higher priority. Although handset vendors also have a vested interest in bolstering Google’s competitors, they won’t want to spend precious R&D resources supporting niche platforms.

That brings us neatly to the most important question. Will Windows 7 phones become an object of desire for consumers and employees? The cynic in me says that a desirable Windows phone is an oxymoron. But I know people who are so comfortable with the PC Windows ecosystem, that they will be instinctively drawn to smartphones that can easily handle Microsoft Office documents and sync perfectly with Microsoft Exchange.

Moreover, consumers’ fickleness means there is surely going to come a time when iPhones are no longer as fashionable as they are today. Some teenagers are already asking their parents for a BlackBerry in preference to an iPhone. The handset market sometimes moves in mysterious ways and the best Windows Phone 7 models might yet become hits with trendsetters looking to differentiate themselves from the iCrowd.