One more thing about community: many of active members are coming from open source crowd with its mantra "release early, release often". With long gap in releases - and even without any substantial info - we are losing interest.

From marketing point of view look for KDE4 - it was delayed for *2* years if I remember initial projects correctly. Plus for one year more it is barely usable for regular user (although 4.2 is really, really good). In total: 3 years behind the schedule. But with good campaign, blogs, screencasts really showing what is happening behind the curtains they managed to keep interest - even hype beyond common sense. Technical advantage? Well, everything I see today in mobile world looks like some variation of Plasma...