I'm not sure what Lukas' friend was focusing on when labeling Adelaide a "****hole". Although I have only spent a week in Adelaide I struggle to imagine how anyone could arrive at that conclusion. Sure its subjective matter but looking at some 'Livable Cities' rankings (there are quite a few of them), which include some tangible measurements in judging a city, make it a more objective view - Adelaide ranks #5 in the Economist. The only Australian city higher than that is Melbourne. Perth is lower. I doubt a "****hole" would get anyone close to the top ten. Note no UK city is anywhere near the top ten either.
If you want a cutting edge city with a fast pace of life and development sure Adelaide is unlikely to be top of the list however there are so many positives about the place. Like most people advise - judge for yourself when you have been, don't let your first impressions be tainted by somebody's view that appears to have been plucked from thin air.