Just catch the top 3 performances and this is my review:

1) David A
1st song : Nail it. Best of all his 3 performances and the night to me. I really loved it.
2nd song : Average. Love 2nd half of it but starting was not very stable.
3rd song: Nicely sung but not as good as first.

2) Syesha
1st song : This is her best for the night. Love it.
2nd song : Wonder why she chose this song. It is not very appropriate.
3rd song : It was ok for me but nothing special

3) David Cook
1st song : Its a pretty boring song. Just not his usual song
2nd song : His best between 3 for 2nd song but still not at his best
3rd song: Started off have problems with high notes here and there. Ended well. But I do not agree with Simon this is the best of the night though performance wise due to its rock flavour does bring up audience.

Overall David A exceed Cook in terms of vocals. Cook exceed David in terms of stage performance. To me they both equal this round.

Who will be leaving us : I predict it should be Syesha. In terms of performance I only like her 1st song not the other 2. And in terms of fan base the 2 Davids stronger.