So the Raspberry Pi Foundation dropped the Model B+ yesterday, and I've been elbow deep in a pile of ribbon cables ever since trying to figure out what's still usable and what I need to throw in the drawer of shame.
Quick rundown if you missed it: still $35, still the same little green board that fits in an Altoids tin (mostly), but they've reworked basically everything around the edges. Four USB ports now instead of two, which is the single biggest complaint I've had about the original Model B since I got mine back in 2012. I've been running a USB hub off mine just to plug in a keyboard, a wifi dongle, and an external drive at the same time, and it's been janky the whole way through. That's solved now. Good.
The GPIO header jumped from 26 pins to 40, which is great for anyone doing serious hardware stuff, but it also means every HAT-shaped thing I've built or bought for the old header is only partially compatible going forward. The first 26 pins are laid out the same way, so old stuff technically still works, it just ignores the extra 14. Fine in theory. Annoying in practice because I've got a breakout board sitting on my desk right now that I was mid-project on, a little weather station rig with a temp/humidity sensor and a cheap OLED screen, and I'm now wondering if I should just wait and rebuild it around a B+ instead of finishing on the old board. Probably going to finish on the old one anyway out of stubbornness. We'll see.
They also swapped the SD card slot for microSD, which is one of those changes that sounds small until you remember you own exactly one full-size SD card reader and forty microSD cards scattered across two drawers because that's what phones use now. Composite video and audio got merged into a single 3.5mm jack too, so the old RCA composite output is gone unless you've got an adapter. Mounting holes are finally in a sane rectangle instead of the weird three-hole arrangement on the original board, which sounds like nothing but if you've ever tried to design a case or a mounting bracket for the old Model B you know exactly why that matters. I built a laser-cut acrylic case for mine two years ago and it never sat flush because of that.
The part I actually care about most, though, is the power circuitry. The B+ ditches the two polyfuses on the USB lines in favor of a proper regulator setup, and they're claiming something like 0.5 to 1 watt lower power draw under typical load. Doesn't sound like much written down, but if you've ever run one of these off a battery pack for a portable project (I did this for a dumb little robot my nephew and I built one weekend, don't ask), every fraction of a watt matters.
None of this is a huge shocking pivot or anything, it's an iteration, but it's the kind of iteration that makes you realize how much cruft accumulated in a design that's basically unchanged since 2012. I've got two Model Bs currently running as a print server and a Pi-hole-before-Pi-hole-was-a-thing ad blocker (I built my own dnsmasq setup, it's ugly, it works), and I don't think I'm going to rush out and replace either of them. But the next project, the weather station, is probably getting rebuilt around the new board once I can actually find one in stock. Element14 and RS Components are apparently both carrying it and I'd bet it sells out fast the way the original did.
One thing I'll say, and this is a minor gripe that has nothing to do with the hardware itself: I wish the Foundation would just retire the "Model B" naming scheme entirely at some point. B, B+, and there was a Model A and presumably an A+ coming down the pike eventually. It's not confusing yet but it's heading that direction, the same way Android version names started getting cute right around when they stopped being useful as a quick reference. Anyway. If you're in the market for a new Pi and don't already have a shelf of Model B accessories, this is clearly the one to get. If you're like me, you're stuck doing math on whether your old case, your old HAT, and your old habits are worth adapting or worth abandoning.
Going to go finish soldering now. Nephew wants the robot to blink an LED when it's about to walk into a wall, which is a lower bar than you'd think.