I don't know a ton about Shawn Hill, but heres what I do know;
he has had his share of injuries,
TJ in 2004, missed all of 2005,
shoulder issues again last year,
but with that said, he has looked good so far this year.
If he stays healthy he seems like he could be a decent pitcher,
he's a sinkerballer and gets a good amount of grounders.
that plus a decent amount of strikeouts and solid command,
i think he could be a mid to back of the rotation type pitcher.
if your league is fairly deep and you've got the room,
give him a shot, but someone like Shields might be worth a better look.