There doesn’t appear to be too much substance behind the rumor of Google buying Sprint Nextel, but it is somewhat interesting nonetheless, interesting because of the ways it could be both a good and bad move.

Google obviously wants into the mobile arena in a major way – as anyone can plainly see with their Google Phone aka Android aka Open Handset Alliance – but buying a single cellular operator would pit Google against all of the other carriers rather than working with them, which appears to be their preferred method. Why serve up apps and ads on one network when you can potentially do it for all of them?

That said, if for some reason the Open Handset Alliance fails, and perhaps even more importantly, if Google’s bid to purchase a piece of the open spectrum fails, maybe an acquisition of one of the smaller mobile carriers would make some sense. The VoIP Blog makes a good point in mentioning that Google launched it’s own video service before eventually realizing they could not beat the like of YouTube, and instead bought them.

So while it’s unlikely, perhaps there is a little something behind this rumor – maybe we caught a glimpse of Google’s back-up plan.