I've owned this car for about 2 months, and just returned from my first road trip. It took a little getting used to its "heft" compared with the 3 Series it replaced, but now that I'm used to that, and the operation of the iDrive, I really love the car. It's very smooth and comfortable, and has deceptively great handling. I'm still in "break in mode", doing more stop- and-go, and am getting about 27 mpg. The 5 Series is just a joy to drive, puts a smile on my face every time I press that "start" button.
iPod integration, bluetooth phone integration, and yes iDrive (now that I'm over the learning curve)...but the best feature is the way it drives!