I think that most if not all compact system cameras doesn't have IS, the problem is that will make you use higher ISO to avoid blurry images, which would lead to a noisy images.
Does that bother you at all?
No, not really. First, it's only useful in bad light. And in bad light, I would use the upcoming 50mm f/1.8 anyway, which has OSS. The only thing that bothers me is the fact, that every lens with OSS costs more than it would without (how much? I don't know, but I guess it's around 50€).
It may be a little problem with the Zeiss 24mm though, but we'll see.
Olympus has in-body image stabilization. Panasonic and Sony use lens-based image stabilization in some of their lenses. I'm not sure about Samsung, but I think they used lens-based image stabilization as well. Image stabilization is nice to have, but, in my opinion, it is not necessary. With that said, Panasonic and Sony seem to put it in the lenses the would get the most advantage from it and lens-based IS is regarded as the better solution for IS, but in-body IS makes it available to all lenses. It's a give and take.
I don't think it's a problem but I don't really know. Looking at Tamron 18-270 for Sony A-Mount, the price of A-Mount without stabilization is the same as other mount with stabiization. The good thing I can think with camera stabilization is the lens can be made smaller and you get stabilization for all lens. The bad thing is the camera will be bigger.
I think the video angle is an important one. Both Panasonic and Sony pitch their cameras for their video capabilities (and are serious producers of high-end video cameras), and for video in-lens stabilisation is much preferred to in-body (which really isn't used). I would have preferred in-body myself, but I understand Sony's choice, and I see the benefits.
I have cameras with and without image stabilization. Yes, it's a nice feature, but so is high ISO. Another thing to keep in mind is that high ISO gives you faster shutter speed which helps reduce blur caused by camera shake AND blur caused by subject movement.
IS just helps prevent blur from camera shake and isn't as helpful when taking portraits under available light ... unless you have a perfectly motionless subject.
Using any camera properly and getting good results is NOT a casual thing. You HAVE to get a good technique by careful thought and practice if you are going to want reliable results every time......
.....Once was the time when all photographers HAD to do this and most casual snappers produced poor results. Despite all these new developments, I don't see that a lot has actually changed. It's still important to practice a smooth release of the shutter and to get the idea about accurqte focus etc. The trouble with the current digital cameras is that users are so confused by all the 'fleas on the dog' that they can't see which end is the tail!! It used to be that you never used a shutter speed slower than you could safely hand-hold unless you were able to support the camera on something firm, such as a tripod etc.
....Personally, being an 'old git' I don't use the NEX 3 at slower than 1/30 second regardless of the 'IS' ...anyway my main lenses are Canon FD which means there is no 'IS' to use anyway. This all comes back to neve setting up ANY parts of the camera to operate automatically,......I switch off as much as possible and make ALL the decisions and choose all the settings and criteria by concious thought about what I want the results to look like.
I am mostly using my NEX with either alt lenses or the 16mm, so having IS would not help me that much.
If there are eventually lenses like my fantastic Canon 70-200 for NEX, I would rather use those focal lengths with IS. But I'm not 100% sure I'd ever buy into longer lenses for my NEX system anyway. I like the larger DSLR bodies for the long tele range (up to 500mm for my Canon gear).