4 different winners in the last 7 years.
Without a doubt last season and this season Bayern are by far and away the best team, but they have built one of the best squads in a generation, so that is no surprise. Their record last season was nothing short of remarkable, and again this year. And they do that spending within their own means, unlike Barca and Real, who spend far more than they earn and get an unhealthily large percentage of the league's TV rights money.
Away from the top, the league is extremely competitive all round. I remember seeing Borussia Monchengladbach finish 16th, win the relegation play-off and then finish 4th the following season, gaining Champions League football, with minimum outlay. They sit 3rd this season, despite having lost a few star names over the past couple of seasons. Freiburg finished 5th last year, Europa league football. Now 16th with 3 wins in 17, and largely the same squad.
Augsburg are the success story of this season, generally seen as relegation candidates, sitting pretty in 8th, 4 points off EL qualification. A great achievement on a fraction of the budget compared to the teams around them. Hertha are another recently promoted team that are doing well.
I love the topsy-turvy nature of the league, the focus on developing young stars not buying ready-made stars, and the clear will to win with attacking football, not defensive solidity making for excellent viewing.