And they're curling in (cupping) like that, not rolling the other direction? Getting leathery feeling and dry?

I've got a Cherokee Purple with the same problem, it's in a 4" pot (started March 16) - I had started hardening them off, but then we got really cold rainy weather. I left half in the garage, the other half cam back in the house and of those 10, 5 showed signs of wilting and dropping green soft (but not wilted yet) branches, then of the just today started cupping leaves like that.

I just searched, and though I swear I wasn't watering these more than the others (certainly not more than the other 5 in the same tray), looks like it's just overwatering. I guess in my case, the ones in the house stayed damper than the ones in the garage, even though the garage as cool and none of them have gotten much sun since Wednesday.

Here is a link that might be useful: Tomato King disease page

I also found this link from WSU, seems like if your leaves are turning yellow (mine aren't), it could possibly be a virus. But I think my plants are just stressed (quite a few of them are umbrella-shaped with drooping leaves after this week, the last night in the garage got a bit cool around 50). Possibly that's all it is with yours.

Here is a link that might be useful: Physiological leaf roll