In my social circle, nobody really talks about OSs or technology, but the few complaints I have heard have been about Vista being slow, aero not working, drivers
nonexistent, incompatibilities, features being knocked off of OS X, etc. All of which are true to an extent. Vista itself wasn't a bad OS, but it's deployment was bungled by MS, OEMs, and peripheral manufacturers. The percent of computers sold at launch that were Premium ready was extremely low (I think around 10-20%)
People just didn't get together and decide to all hate Vista. There were very legitimate reasons. Many of which no longer apply years later, but at the launch were pretty serious.
It details the entire ready vs premium fiasco. About mid-way they discussed how all of a sudden laptop shipped shots through the roof and the average computer price plummeted, dragging down specs, something MS was blind to until too late.