My iPad has been sidelining my MBP for some time. Installing the public beta of iOS9 - which includes cmnd. + tab switching between apps - accelerated that trend. And increasingly, I'm using Siri / voice input for more and more stuff. Now my biggest frustration is that my physical keyboard doesn't include a mic. button like the iPad's onscreen keyboard.
If anyone from Apple is reading this, not that you've got two empty spots on either side of the up arrow. The other one would be fine for emoji ;-)
Apple's latest design removed those empty spots.[1] But don't despair, you can already get a lot of what you want without dedicated buttons.
To open an emoji menu in OS X (10.10 or later IIRC), just focus on a text input and hit ^ + ⌘ + spacebar. You can also search for other unicode characters. "⌘" is a little tricky to find, since it's named "place of interest marker" or something like that.
OS X doesn't yet have Siri, but it does have Dictation. I assume that when Siri replaces Dictation, the typical keyboard shortcuts for toggling it will stay the same: double-tapping fn or ⌘.
There are times when Xcode chugs on a top of the line 2015 15" 2.5Ghz rMBP with 16GB of RAM and a 2GB/s PCI-E SSD. Not frequently mind you, but it does happen. It's incredibly heavy and I can't see it being usable on an iPad unless Apple manages to magically pull out an A-series CPU that's in the same class as a Haswell i7.
If anyone from Apple is reading this, not that you've got two empty spots on either side of the up arrow. The other one would be fine for emoji ;-)