I was wondering the same thing! HTC had a battery widget with Froyo on the Evo 4G and I loved it. Simple and always accurate. I have tried 3 different battery widgets from the market and all of them have given me problems.
This dosen't give a percentage but it should be accurate enough..got to Settings then to About phone...should be at the bottom...then Battery...there are 10 bars there that should be helpful enough for now.
my battery seems to be stuck on 99% according to the widget, should i keep charging it till it says 100%, the red led never turned green yet, or does 99% mean its fully charged
I do think this is a potential bug... I have seen a few ppl mention, as well as myself, that when you use a widget it sticks on 99% for a long time.... Dont know if its a kernel thing or what but its definitely not right
I never liked the batter widgets taking up space on my homescreen so I installed an app called elixir. It gives the option of listing phone info in different sized widgets, but I use an option to display the battery level as a pie graph in the notification bar (you can also use a bar graph). Then when you pull down the notification shade, it lists the % and tap to open the app.
If you use Beautiful Widgets, they have a great little battery widget, it is small 1x1 size, and is a picture of a green battery with the % below it, and you can click on it and takes you to the battery settings screen.
I love this widget -- it's tiny and lives in your notification bar. (It's not in the market -- it was posted on Good and EVO a while back, linked from XDA.) It works great on the 3D just as it did on the 4G.