Hello and welcome to the Cameralabs forums.
We place higher weighting to JPEG examples and performance in our tests simply as a reflection of how most people will use the cameras. While RAW files allow you to get the most from a digital camera, the fact is the majority of owners will shoot in JPEG, so that's what we test the most.
That said, we have published a selection of RAW results for the Sony A100 and Canon 400D, and will also do so for the Nikon D80 and other key products.
You're right that noise levels can be affected by the image processing, but generally only in terms of noise reduction. We aways comment on noise reduction and where possible, state when a specific NR mode has been applied. It is still however valid to measure and judge noise levels of an in-camera JPEG as an indicator of the camera's inherent noise performance.
As for Image Stabilisation, it may allow you to handhold at slower shutters, and therefore avoid noise by using lower ISO settings, but there are times when fast shutters are demanded - such as for moving subjects. Or times when the light is so low, both stabilisation and high ISO are required. There's also the fact that while the Sony A100 features built-in anti-shake, most owners of entry-level DSLRs will be using kit lenses without stabilisation.
These are all reasons why high ISO performance is very important, and why we continue to place great weight on these results.
I hope that explains our position, and that you still find the reviews useful,