Anthony Watts has republished Hausfather (Mosher) et al's poster for the AGU fall meeting in San Francisco. It covers the urban heat island effect and is based on a better determination of which stations are urban and which rural.
Urban stations are warming faster than rural stations on average across all urbanity proxies, cutoffs, and spatial resolutions examined, though the underlying data is noisy and there are many individual cases of urban cooling. Our estimate for the bias due to UHI in the land record is on the order of 0.03C per decade for urban stations. This result is consistent with both the expected sign of the effect and regional estimates covering the same time period (Zhou et al 2004) and differs from some recent work suggesting zero or negative UHI bias (Wickham et al, submitted).
Zero or negative UHI always struck me as a bit daft. This result seems intuitively much more sensible to me.