As for the braves....
No way that Salty is going to be involved in any trade talks. As for Escobar, he is a bit expendable because of the good depth coming up through the system at SS. Brent Lilibridge is an interesting prospect in AAA as he presents the total package- a player who hits for average, has some good pop and is a beast on the basepaths. Played college ball at Washington and in 2006 was one of three collegiate players that had double digit HRs, 50+ RBI and 50+ SB (17 HR, 71 RBI, 53 SB). He just offers more than Yunel.
Another prospect is Elvis Andrus, a very very similar player to Lillibridge but is only 18.
Question:The Braves need a franchise 1B. They have two catchers with good defense and size. Only one can start. What do you do?
Answer:
A. Trade one of them for
risky pitching prospects
B. Trade one of them for an
expensive pitcher for the stretch run
C. Move one of them to 1B and enjoy the security of having a franchise player at both C and 1B
D. If you didn't choose C right away, please stop watching baseball
Thats fine and all but doesn't necessitate that can't simply dangle one of these prospects in return for some good starting pitching. Yunel isn't the prospect that Lillibridge is. Or that Elvis potentially can be.

EDIT(1): Salty does have some experience at 1B.
EDIT(2):

At Buehrle being risky.
You are a joke.
EDIT(3): If the Braves don't invest in some SP, they risk losing more ground to the Mets, who have already taken measures. As such, the Braves have little shot at the post season if they don't win the division outright.
Wait, wait, wait. I'm a joke for being down on a pitcher who had a 4.99 ERA last season and has 6 seasons of 200+ IP on his left arm already AND had arm trouble last season?I was going to be civil, but if you're going to insist on being a tool, then two can play that game.
So I suppose it would be a bad gamble to make a play for Randy Johnson? (5.01 ERA last season, arm troubles, 14 years of 200+ innings)

Puh-leezeThere is risk associated with taking on any contract. However, I associate risk with trading for a player with 19 games of major-league experience much more than a proven veteran that has proven himself as a SP for many years, is good for 10+ wins and a 3-4 ERA each season and is expendable at the end of the year if he can't perform.
Simply put, he gives the braves much more of a shot NOW at getting into post season play. With Lillibridge in AAA we can afford to let Escobar go and not expect much of a dropoff.
EDIT: Not trying to be a tool but you are dramatically overvaluing a single prospect and not putting enough stock into the consistency of Buehrle.