As far as I've seen, there is no review out yet for the Sigma 18-200 WITH anti-shake. I'm a lucky owner of the Nikkor 18-200 with VR and I absolutely love the VR (aka anti-shake).
If you're on a budget, I'd suggest
(a) either waiting for a serious review of the sigma with anti-shake and decide then
(b) or buying the 18-135 kit lens and reselling it later when you can lay you hand on the Nikkor 18-200 VR
(c) or extending it with the nikkor 70-300 VR at a later point in time
But don't forget:
1. Anti-Shake is also very helpful in the sub 135mm range, even shooting with 18mm in very low light conditions (aka "vllc"
2. with 18-200 you normally don't have to change lenses, losing precious time, and/or carrying other lenses around or worse leaving them at home...
So, my personal recommendation is (b)
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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