FWIW: I have essentially zero interest in a lens without IS, even though I use a tripod and monopod quite a bit.That's not how I feel for shorter focal lengths but given the 24 IS, 28 IS, and 35 IS plus Nikon's 16-35 stabilized wide angle lens, you're clearly not alone. Is your interest in IS at these focal lengths for video or some other type of shooting? I understand the benefits on paper, but would like to know how people are taking advantage of IS when they shoot.
For the types of video projects I do (mostly run and gun travel stuff) it becomes essential to have IS because running around with a Steadicam mounted with a vest is just too impractical. It's the reason I keep my 60D with 17-55 f2.8 IS around (light weight and small form factor)...while my 1DX and 5Dmk3 are clearly superior cameras in both photo and video.
For photos I'd much rather have a faster lens than one with IS. Hand held I'm able to get a 50% hit rate at 1/8 of a second without IS. With a 1.4 lens at ISO 12800 that's almost like taking a properly exposed photo in darkness.