I have to agree, Not saying bounty hunters are the least played.. But they're definitely being pushed to the side by all the Mercenary's (On my server the Red Eclipse EU) every bounty hunter i come across is usually a Merc.
I tend to agree that the Operative is a class i rarely see anymore especially a DPS in WZ. I was leveling a BH PT until i witnessed them all being leveled so i switched back to my Op. I prefer playing the rarer class, makes me feel special ^_^.
I've actually noticed the opposite. I see a lot of powertecs, but not many mercs. I see a lot of marauder/sents, followed by sorcerers, then jugg/guardians
Don't see many troopers at all, particularly vanguards, or many consulars, particularly shadows. Ops are rarer than snipers, but neither are common.