I wondered where Lionel was also, but then he and Lex don't get along. Loved Clark telling Lana, Come on, you don't even know most of these people--so true since we certainly didn't.
I wondered also if Lex is sterile. Maybe he implanted some of Clark's sperm, retrieved during one of the many times Clark's been knocked out. So he'll have Clark's baby? Not implying Lex is gay there, more for the experimentation to see if Clark's kid has superpowers. And then he would have something of Clark's, something Clark never even got to have.
On the other hand he does seem to be fond of Lana... nice humanizing moments between them, which are kind of blown by the idea he's experimenting on her.