Hmm...

What I really hate about Android is
- the lack of mutlitasking - I freaking don't want anyone to close my apps. I am the one in control!
- the amount of malware - hell, you need an antivir on Android! It's becoming Windowsy even more
- afaik you can't do package management on the command line (apt-get/zypper)

Can one use the core Linux utils in the term (tar, find, grep, wget) on Android?
Is it possible to build any given C/C++ app (even the terminal one)? Assume I'd like to build Haskell/Brain****/Lisp for it.

As for what endsormeans says. The dealbreaker are the drivers. We have so many foss OSes. Ubuntu Touch, Plasma Mobile, FreeMantle (possibly), even Debiancould fit. But the first two work flawlessly on maybe 6 devices, none of them having a hw kbd. With the needed drivers and an unlocked bootloader we could have anything anywhere. So a device which supports the mainline kernel could fit.