A bit is a micro-bitcoin. This leaves two decimal places...
Now that's just silly.
I don't know anybody that uses the word in that way. That seems like a great way to cause confusion.
With that usage you can't shorten the word "microbitcoin" to "microbit" in conversation, since microbit would apparently actually mean micromicrobitcoin? Bah, that's just ridiculous.
I think I'll stick with the usage I hear regularly.
More people are using 1 bit = 1 uBTC than 1 bit = 1 BTC. Have a look at r/Bitcoin. It makes more sense if we make the assumption that bitcoin gets popular in the future and practically no one will have a whole bitcoin.
It's a good solution to quite a few problems.