Well nothing to do with the preview but still good news (well for the CW) is the ratings of Thursday since Smallville is no longer airing on Thursdays.
The last three weeks Supernatural (it happened once last year) has aired back to back episodes in the 8pm and 9pm hours.
* I will be mentioning Smallville's summer average and Supernatural's summer average. Both of those refer to the average viewers of the summer reruns before Smallville went to Fridays. Smallville's lower performance on Friday (which was certain to happen) is not considered.
And how have the results been. In its first week, the 8pm hour decreased a mere 70,000 off of Smallvilles summer average, and the 9pm hour actually increased 30,000 0ver the normal Supernatural hour.
2nd week (and with it not airing in the 2nd largest market LA), at 8pm it was only 10,000 viewers off of Smallvilles Summer rerun average. At 9pm it was up 20,000 over the average. So the night was officially performer over the average night of reruns when Smallville was the lead in and without the nations 2nd largest market..
3rd week (last night) Supernatural didn't air in the largest market in the US (New York City), and at 8pm not only out performed Smallvilles Summer rerun average by 300,000 viewers) we had the highest summer rerun for the CW. And at the 9pm hour we were up over the average Supernatural rerun by 450,000 viewers, and its the 2nd best performance by a rerun for the CW this summer. And both of those numbers are without New York City.
Based off of this (especially telling that two of the weeks had major preemptions) and the one time it happened last year it is clear that Supernatural was not dependent on Smallville as a lead in. In fact Both hours on average (including last years occurance) are performer stronger.
I really wish we would have gotten the 8pm hour (and no they could have gotten away with everything they have done at 9pm in the 8pm hour, times have changed dramatically).