So I installed this the other day. I hope this is the base that they will be updating. It looks nice, and seems stable, however as some have pointed out, we loose the efficiency and last trip details. Secondly, it doesn't seem to track/know about charging session. This was the real reason for updating for me. The app still hasn't detected that I have charged, even though it says it is up to date.
The second problem may not be the apps fault, but the most useful thing is it tells you at the top what the current battery and range estimate is. Now the battery percent is accurate (I would be very worried if they couldn't get even that right), but the range is even worse than usual. I had a quiet week, so was at 55% still left with only 117km done this week. I charged to 100% as I usually do and got - wait for it - 144km range predicted. This is quite possibly the worst prediction I have ever seen. Now 117km from 45% of the battery give a total range of 260km. Even multiplying by the EPAs dodgy 0.7 fudge factor gives 182 km for a full charge. To indicate 144km (89 miles) is out by over 40%. It is getting worse, not better. At this level of incorrectness, you might as well remove the feature completely rather than indicate such a totally wrong value. I am hoping that they have incorrectly got miles switched with km as 144 miles would be a bit low, but still in the realms of possibility.
So, unless you really dislike the old app's gui, the new one really isn't worth updating to in my opinion.