As a N900&N9 user I have never felt "lack of useful apps". On the contrary - predominant majority of Maemo 5&6 apps are USEFULL, when it is just the opposite with iOS&Android. The only thing lacking in app availability for Maemo 5&6 are apps build for big companies/services like BMW, Eurosport, Philips, Unicredit etc. They all do it just for iOS&Android.
But the community we are in is doing great job in filling those gaps!