I'm currently driving a BMW 530d Touring (G31) for the week. It's pretty well loaded and is the M Sport version. It's the second time I've driven the latest 5 Series, the first one being a G30 520d. On the long journey on Monday night I decided I'm not impressed at all. It's not a bad car by any stretch but it just feels dated already. The interior isn't particuarly "warm" if you know what I mean, and the ambient lights at night give it a very austere feel. The fuel economy is not great either. It's low 50's for the 520d* (which is pretty good), and low to mid 40's for the 530d. The E-class models I drove were mid 50's. It has the full black panel display but it doesn't feel particularly modern. The A4 virtual cockpit I've driven a few times and the E-Class widescreen cockpit feel much more modern.
I can't explain it really. I love BMWs generally, but I'm wishing I'd taken the E 350 wagon they had, which had the full widescreen cockpit.
I also think the G30/G31 is looking very dull already. It's an utterly generic BMW, and the front 45 angle view is pretty ugly.
These are just my opinions, but I'd take the E-class over the 5 Series now.
EDIT: *I misread the data on the 520d in my records, and I actually got low 50's. Initially I wrote mid 40's.