When I first saw a salute in chat it was 07. After thinking about it and seeing many different renditions I personally chose <o.
The reason I chose <o over the others has to do with how the others look. Don't get me wrong I'm not telling anyone how to salute. Nor am I making fun of anyone's salute. Any salute given in any style is a sign of respect for your opponents and team mates. I just believe there are flaws with the other methods.
07, 0> and o> are backward. You are saluting the other person, therefor they are looking at your characters salute to them. As I look at these I see a left handed salute.
<i looks to me like the arm is coming from the hip of the person saluting.
<0 looks like the arm comes from the chin of the person saluting and the person saluting has a massive head. This one does run a close second to the one I believe is best though.
The process of elimination leaves me with <o as the most believable and esthetically pleasing form of a typed salute in my opinion. However as is the case with every opinion, I could be wrong and will undoubtedly be told so.