I don't have my Superfly record here (that was my very first album I bought with my own money . . . way back when I was in the 8th grade!) So my memory is a little hazy on the exact intros for all his songs, but I think you're hearing either bongo or high conga played by Henry Gibson (Curtis Mayfield's percussionist.)
The technique is one where he'll put his thumb or palm on the drum head and either move it towards the center and/or push down harder. This changes the tension on the head, which of course raises the pitch as the head is struck with the other hand. There is another technique where you wet your thumb, strike the conga and slide the thumb towards the center of the drum head.
If these don't sound right, let me know and I'll check out the CD at home to be sure I'm remembering the right intro.
It's funny to remember that in junior high, I wanted to quit piano and be a percussionist, I liked Henry Gibson that much. And I was convinced I could sing just like Curtis! I have no idea how my family kept straight faces when I practiced, especially as this skinny small-town white kid was singing a bunch of black power songs!
I don't know what a "talking snare drum" is, but I just listened to the demo on iTunes and hear a bongo played with a stick (possibly a rattan stick). At least it sounds like it was played with a stick - it could just be EQ-ed up a lot (I don't think they had Aural Exciters in those days, although it's possible that they did).
If you're hearing a slide, that's a conga trick - you push down while sliding your thumb from the edge to the middle after hitting it with your other hand. It changes the pitch of the harmonic sustain.
Pusherman came out in '72, too early for syndrums, and that's defintely a skin head, not a synth. I'd vote for Roto-toms but '72 sounds too old for them even- anyone know? My guess is that it is actually the stick-push head-tension tuning trick but being done on a bongo, not a conga. It's pitched too high for a conga. A bongo would sound pretty much exactly like a Roto-tom and if the head was loose you'd get that much pitch-change at that high a tuning.
Now if I were going to re-create it today a Roto-tom would be the obvious way to do it and is probably what's on the live version like Nick said.