Rick Helling has most likely beat out Hentgen for the last spot in the rotation. He's had a decent spring with an ERA under 4 in 23 innings. The rotation is shaping up like this:
The only starter worth having on your roster is Lopez, who has followed his breakout season with a very strong spring. Ponson was having a decent spring until his last 2 outings, in which he got shelled, pushing his spring ERA over 5.5. Not pretty.
Julio has had a dominant spring, allowing only 3 hits in 8 innings, while striking out 4. He is a solid closing option after the top 10 or so guys are gone. While he won't post more than 30 saves on the O's, his ERA and WHIP will help, and he gets decent K's.