I think the "Superstorm of 2010" is a pretty appropriate title for this event, barring any significant changes (hell, they're already down to 983MB in central SD). Both the GFS and NAM are now in agreement that we'll be looking at a 955-960MB low, which would definitely be the strongest Great Lakes storm in [recorded] history. I'm not sure how I feel about the 1978 Superstorm being in the running, as it wasn't a typical "Great Lakes" storm... even so, this current event will be giving it a run for its money.
Both the GFS and NAM have been consistent over the past several days in spreading extremely strong surface winds across the region Wednesday, as mixing layer heights skyrocket toward 800-750MB. Within that layer, there's a pretty substantial wind maximum on the order of 60-80knts, pivoting through the region. Over MI, BUFKIT is showing 70-75knts at the very top of the mixing layer (highest magnitudes I've ever seen over this area), with 45-50knts easily being tapped into.
I suspect most of the high wind watch region [Dakotas to OH] to experience solid 50-60MPH winds as time progresses from late Tuesday through the day on Wednesday. I would not be at all surprised to see a few isolated locations report 80-100MPH gusts, particularly along lake shores susceptible to SW / W flows. The November 10th, 1998 storm produced several gusts of that magnitude.