I haven't written about FON in a while. It's still an interesting idea, but I fear that the execution of that idea is too weak to make it successful. If they succeed it will be the triumph of the idea over the execution.
But today I saw this post in Martin's english blog which just reminded me of the major source of their problems: signups vs. conversions. FON has long been big on signups. They love to report people with an account, people who have requested a free fonera, people who have done the easy part. What they need to focus on and write about is not the signups but the conversions! How many of those people who spend $5 on shipping actually turn on their fon?
The strength of the network is in operational access points, not in the accounts or in the free routers that sit in their boxes to never be plugged in. The "Fonera Promise" is an empty promise - there is no reliable motivation for the Linus' of the world to actually plug in their fonera and hence this remain a competition of paper tigers until FON starts focusing on the actual active access points in the world.
Based on the stories I've heard of Martin's past (pump and dump of various companies) it seems more likely that FON will continue pumping up their buzz using these empty numbers about signups and then sell out to someone else before others realize the true situation: conversions are lower than signups...and in the case of FON those conversions are likely lower by a large amount.