When I was recently on vacation I visited friends and incidentally they all lived just outside of smaller towns on the countryside. They all had a DSL line at home but mobile network coverage was weak at best. Apart from being a nuisance for me they said themselves that they were not happy with the mobile network coverage in their house. And it was not like they were living in totally remote areas. Perfect places for femto cells!
So while femtos haven't really made a big inroad in most countries over the years so far, I still see the potential and the need, especially since people more and more use their mobile phones instead of fixed line devices for voice calls. Sure, Wi-Fi and SIP clients could also do the trick on their devices when they are at home but it's not seamless and doesn't work for their guests. Fortunately, Vodafone seems to expand their femto solution to more countries beyond the UK now so let's see, perhaps that might be a solution for such locations and perhaps a reason for the competition to wake up.
In my eyes the greatest potential for femtos lies in public places. I know many bars, restaurants and stores that lack coverage and would be happy to put up a femto to provide coverage to their customers. Last week I actually found myself avoiding an uncovered restaurant because I expected an important phone call that wouldn’t have reached me otherwise. Another example is a large nearby hospital with 700 employees of whom many avoid two operators just because few parts of the ground-floor (including the emergency room) are not covered by them. My girlfriend was made aware of this already on her second working day and immediately decided to change networks despite her ward was not affected.
Femtos are a huge opportunity for operators to get their coverage improved at negligible costs where people stay most, indoors. Instead of selling femtos and even demanding a monthly fee, like Vodafone does in Germany, I would set myself apart from other operators by giving away femtos to businesses and ask them to indicate coverage by a window sticker which would also be effective as publicity for superior coverage.
SFR in France gives a Femto for 49€ (refunded at first use) to post-paid customers. The femto is closed to a group of lines for legal issues.