Getting the Yoshi ride AND keeping ET? Sounds like a homerun to me. ET was a surprise for my girlfriend and I on our trip in October. A little campy, but fun. I loved the whole feel of it, and it made me wish I had been able to experience Universal Orlando so much earlier. And obviously, the Studios park can use all the non-screen based attractions you can throw at it. So keeping ET and adding more practical effect rides is a win-win in my book.
But also, if it's staying, please give ET a proper refurb.