A day after Nikon introduced their new AF-S DX Nikkor 18-300mm f/3.5-5.6G ED VR super zoom lens, Sigma announced a refresh of their 18-250mm f/3.5-6.3 DC Macro OS HSM lens for Nikon mount. One of the new added features is macro capability. The Nikon mount version of the lens will start shipping in July for $499 (vs. $1000 for the Nikkor 18-300mm).
MTF charts of the Nikkor 18-300mm and Sigma 18-250mm lenses:
Wide MTF charts
Tele MTF charts