Here is some news I recently picked up while in Oxford regarding the next generation MINI (aka R56) due out in 2006-7.
The model range will expand to four petrol engines for the next iteration of the MINI. Further with the angle of the engine will be changing and the front frame will have to be redesigned in order for the engine to sit lower in the car. As you can see the in photos of a couple recent (one & two) test mules the new engine doesn't fit very well in the current frame configuration. Because of that engineers have had to create a rather unsightly bulge to attain the proper engine clearance with the hood. It's assumed the redesigned frame will allow for the engine to sit lower in the car and avoid this rather awkward look.
The MCS will drop the supercharger, add a turbo and will have around 180hp on tap from, what looks to possibly be a 1.8L engine. This was the first time I had heard about the 1.8L engine being used for the MCS – before I had understood it would again be using the same 1.6L engine as found in the Cooper but with the added turbo.
I wasn't able to confirm how MINI will break up the rest of the range but we do know that MINI has listed a 1.6L for all the other petrol models. All we have to go on is this list of the engine specs that was leaked last winter. If correct it looks like the R56 Cooper will be around the same HP figures (in both CVT and manual guise) and there will be a sport model of some kind at around 140hp. It looks like all petrol engines will be DOHC. It's also worth noting that these numbers could vary and seem to be only initial targets.
Cooper/One could be released first in late 2005 or early 2006. The MCS will probably follow that with a late 2006 or early 2007 launch. This isn't 100% confirmed but when I asked someone in the know about these time frames they simply smiled and seem to nod approvingly.