I think it is more than just Broadcom hype, but the first affordable computing platform for tinkerers, revolutionary as the Arduino did for the electronics platform for DIYers. The Raspberry Pi sold more than 1 million units and therefore it has a great community. All the other cards are clones that, while they could be more powerful, they also are much less supported.
The RPi is powering my SD3 just fine with a touchscreen HDMI LCD and a modded OctoPrint. It is surely much less responsive than the Android app used by Qwims, given its architecture - it is a web interface running on top of a Phyton server after all.
And Beagleboard was out of the game before the Beagleboard Black, because they were simply too expensive. Now that you can have a Beagleboard Black for more or less the same price of the RPi, considering that you don't need a SD card, it may be preferable, and I think I'll buy one of it to give it a try. There are more GPIO pins and the RPI is almost twice as fast as an overclocked RPi.
It is clear that the RPi is now quite outdated and there are superior alternatives, but the RPi is still an excellent choice for many DIY projects

Great idea, and very polished implementation.  Good job!

I hadn't even thought of using an android stick; I have an extra one laying around the house.  I may try that while I'm waiting for Adafruit to get more TFT touchscreens for Raspberry Pi's in.

Most sticks use hdmi, mine has a Av out port and hdmi. So I can basically use any screen.

Well, given that a RaspberryPi runs @ 700MHz, and nearly all android SoC based systems (well, A10, A20, Rockchip, i.MX et al) are going to be 1GHz+ (usually 1.2-1.6)... as well as having far better 3D acceleration et al... You will find that a android stick loaded with linux will out perform any RPi solution - even if you leave it running Android!

RaspberryPi's are merely marketing guff from Broadcom (I mean, the guys who set it up are even ex-Broadcom employees).. and I do applaud them for achieving the marketing success they have... But hardware spec wise - They are vastly inferior to numerous alternatives out there...  They don't even hold a torch light to a Beaglebone Black what with its 2GB onboard flash, 3D Acceleration, 2 x Programmable Realtime Units (read, 32-bit microcontrollers) ... etc etc etc.. RPi's are really not the ideal choice for anything other than.. well.. their target market... Education (in the same way that 'Logo' is great to teach the principles of programming - but thats it ) .. If you want actual credit-card-sized computing - there is loads of better alternatives that are just as accessible as RPi's...

But you do have to commend them on their marketing job (which was originally bootstrapped by Broadcom; wonder why??   )

I hadn't even thought of using an android stick; I have an extra one laying around the house.  I may try that while I'm waiting for Adafruit to get more TFT touchscreens for Raspberry Pi's in.

The lcd is run by an android tv stick, specifically the mk808c. The application used to print is called gcodeprintr and can be purchased in the google play store. Now this app can only run gcode, so I still have to slice my models on my computer, but you pretty much have to do that with all lcd setups. I use dropbox to transfer gcode over the the printer which works wonders.
To control the lcd I am currently using a computer mouse, I will probably change that soon as I'm still doing some testing.

All in all this is so much better than having to use a computer! anyway, just wanted to share, let me know if you have any questions.