Okay, thought this would be interesting so I thought I would kick things off.
Lifts that I believe to be over-rated:
1) Tricep Dips, It may just be because I weigh 240lbs, but dips have always seemed to be more trouble than they are worth for me, I always end up having trouble staying stable, thus turning it into a total upper body exercise as opposed to focussing on the triceps. Plus it's caused one of the only injuries I have had since I started training (straining one of my wrists)
2) Hypers - I really have no idea what weighted hypers are going to do for my lower back that isn't done by deadlifting and or squatting, yet they seem to be one of the in-things in my gym at the moment and with a lot of strength coaches.
3) Dumbell Flies --- in fact a lot of dumbell work done by people who are not yet strong enough to even hold the dumbells over 20kg's.... Until you obtain a good strength foundation which is easier to build with barbells and machines, I think you might as well stay away from dumbells for a lot of exercises other than perhaps curls, and dumbell bench. Certainly no point in a begginer doing lat-raises, and cuban presses e.t.c with 5kg dumbells.
1) Rack pulls - NOTHING and i mean NOTHING has helped my back and me to get my deadlift up like rack pulls. It also helps get your body accustomed to a heavier weight, giving extra confidence for that next deadlift pr attempt when you know you have rack-pulled 100lb or so more than it.
2) Tricep pushdowns -- Very few tricep movements allow me to focus as intently on the quality of the movement whilst still using appreciable weight as pushdowns, i'd make them a no.2 tricep movement behind close grip bench presses.
3)Some machine work.. Sure how dare I, right? Blasphemy. Well actually, some machines are great. I absolutely love the HS bench machines, the T-bar row machine, hack squat machine, rowing machine, I also use the smith machine from time to time, hell i even like the pec-dec, and the preacher curl machine!!
I hate all this machine-phobia that goes on. OF COURSE, you should be making the basics, ie pressing, pulling squat/dead/bench/mil/row/curl e.t.c the basis of your program (unless you are already so advanced that it is simply to high a workload for you without risking injury) However, machines make absolutely great finishers, just to keep getting that bit extra out of your workouts.
So what do you guys think... what's over/under-rated?