Windows Phone 7.8 upgrades appear on Nokia's servers for all eligible Lumias

Lingering concerns that Nokia might not upgrade all its Windows Phone 7.5 roster to 7.8 might have just been put to rest. Just a day after updates for the Lumia 510 and 800 were caught on Nokia's servers through NaviFirm, updates have also been spotted for those devices that didn't make the initial cut: the Lumia 610, 710 and 900 have all appeared, each with numerous region-specific updates in tow. Their existence still doesn't constitute a formal update, so be aware that you're gambling with yo...