I admit it, I’ve got nothing for you guys today. Tuesdays are long, tedious, and boring.
I do think it’s interesting that AC Transit has so many different kinds of buses in its fleet. Let’s have a look, shall we?
Exhibit A: Old Bus. Yawn. This guy has the pull cable to request stops and hard plastic seating with maybe a bit of upholstery. On the plus side, the windows vent generously. Also, there are bars running the length of the bus for standing passengers to grab onto, a feature which some of the newer buses are strangely lacking in.

Bor-ing.
Exhibit B: New Bus. Cushier seats. For some reason the handicapped reserved seats are on risers you have to step up to get to, which sort of defeats the purpose of being handicapped-accessible. The wheelchair section design is much improved; by default the seats are in the up position rather than having to be manually put up or taken down. Buttons instead of a pull cable to request stops, which is annoying if you have to reach across 10 people to hit it. Instead of kneeling, these buses are already closer to the ground, so they just lean over a bit if need be. The wheelchair access ramp is much cooler, too.

Hey, what do you know, it's my bus, the 51 - pretty blue text makes it easy to spot.
Exhibit C: Rapid Bus. Ooh, snazzy. These guys run on the Rapid routes (big surprise). They’re like the new buses, but somehow cooler because you’re practically speeding down San Pablo.

Zoom zoom! It's the 72R!
Exhibit D: Low Emissions Bus. Again, just like the new buses, but they’re a bit shorter and taller. Kind of squat, really. Only two doors instead of three.

My other line, the 52L! Easily recognizable thanks to the red text.
Exhibit E: Transbay Express. Has wifi and goes across the Bay, that’s about all I know.
I've never been on one of these guys. I imagine the Express buses are like paradise.
Exhibit F: Zero Emissions Bus. Oooh, showing up Exhibit D, are we?

Showoff.
Exhibit G: Articulated (Double) Bus. Take two new buses, stick them together accordion-style, and you have a hell of a ride if you stand in the midsection. Somehow manages to get packed anyway on the 52L morning route. Often found running Rapid lines, as seen here. Sometimes if traffic is backed up, they’ll make a left-hand turn and end up blocking entire intersections!

There have been times I've been at the front and not even realized a friend was sitting in the back. These things are huge.
That’s all I can think of – any others I’ve forgotten?
I LOVE YOU
Check out our whole fleet online: http://www.actransit.org/aboutac/ridershipbusfleet.wu
Awesome! Thanks, AC Transit!