Hot Lava (or an iteration thereof) has been a color for every car so far (except the xA) in the Scion lineup. Also it was a release series color for the xB1, xD, tC2, and xB2. Also it is a stock color for the FR-S and iQ. That being said, I wouldn't be surprised if the Release Series iM is the same or a similar color. I look towards the JDM Auris "RS" trim. **
LINK**
I think the stock iM will be/is based on the version in the link. I think there will be a few changes to it for the US version, but pretty close to that car.
I doubt the panaramic roof will be on the iM Release Series, but I don't doubt the wheels, fogs, spoiler, and from the link the orange seats, and stitching. Also the smart entry where you just touch the door handle and the car locks/unlocks automatically.