I didnt notice anyone mentioning in this thread that the saw is a good wep for distracting the enemy team (CTF), if you rush in first and move illogically (even when not attacking directly but just running around in their base and making them chase you), theyll be busy dodging you and wasting their bullets when the rest of your team arrives and shoots them in the back.
Another good technique is running from your enemy who uses a gun, wait until he disappears from your screen, then change direction rapidly and if possible boost yourself back with a nade, most times he will be still running towards you at max speed thinking HE is chasing YOU...
Ive also noticed that sometimes when i suddenly start using the saw in the middle of a CTF match, and kill many surprised enemys, then in about a minute 2-3 guys are using the saw also, then you can surprise them again and play defensively with a gun.
In conclusion its a very creative wep, but im really sad since in 1.5 a lot of times the saw doesnt register.