If your bakeware has been refrigerated or frozen, then I could see letting it sit out a bit before putting it in a preheated oven. But it it hasn't, I don't see a problem.
Here's the actual answer about the temperature difference from TT's FAQs:
<h2>Is it safe to go from the freezer directly to the oven with temp-tations
®?</h2>
Yes, all temp-tations® bakers can go from the freezer directly to the oven. However, when doing so, allow your temp-tations® baker and your oven to heat up together. (Put the stoneware in an unheated oven, turn on the oven, and allow both to come to desired cooking temperature simultaneously.)
I just found this info on Rachel Ray's site. This is what I do with my non-TT stoneware:
This stoneware is oven safe to 500°F. (Some pieces may have silicone on the lid handle which is only oven safe to 350°F) Quick changes in extreme temperature could cause thermal shock causing your stoneware to crack. If moving stoneware from refrigerator or freezer directly into hot oven, the temperature should not be set higher than 350°F. or the stoneware may crack. Always make sure stoneware has warmed or cooled to room temperature before placing in the stove, freezer, refrigerator or under cold water in the sink.
~Who in the world am I? Ah, that's the great puzzle~ Lewis Carroll, Alice in Wonderland