My picks as follows thus far:
Symonds - recalled to the squad under pressure, not an established starter & had not produced the goods previously. Came in with the team in trouble and the quality bowling attack on top. Produced a match winning knock & finished not out. Innings showed all aspects of what he can do, but most importantly he showed the required mental approach so often missing from his batting.
Styris - much of the same reasons as for Symonds. Debut ODI century to go with only 1 previous Test century, with an ODI average of only 20. Came in when NZ were 3/15 and chasing a big target, & scored at a better strike rate than Jayasuriya in the same match, if not the other contender's innings as well! While the SL bowling attack does not rate as highly as either SA or PAK, they were better suited to the pitch conditions & bowled better than the NZ attack, whereas the other matches bowlers were well matched under their conditions. Errors in the NZ selections made it difficult for him to have partners in the lower order & tail capable of staying with him. Ran out of support with too much to do & self destructed with the tail enders - meaning he would have probably scored higher & got closer if he had support. Produced a lone hand throughout the innings. The only reason I do not rate his knock number 1 is that he was out & NZ lost by 47.
Lara - great come back. Set the innings on it's way to a winning total, although Klusner gave it a good scare to get SA within 3! Lara was all class and was a big part of the upset result over the hosts, but with his credentials it was only a matter of time. Now he needs consistency to show if he is really back!
Jayasuria - had a big slice of luck b4 he got going, then rode it to produce a match winning start to the SL innings. The match could / would have been very different had he been given out, as SL batting tends to follow his results of late. I actually think that Tillekeratene's innings won the match for SL, as he was the foil for Jayasuriya to launch his attack, and the backbone for the rest of the batting to finish not out.
Wishart - possibly the highest score of the tourneyment & batted throughout to finish not out. Looses it's significance in comparison to other innings because of the relative weakness of the opposition and the lack of pressure throughout.