- random strings (xkcd) - longer as all 4-, 5- and 6-letter domains are reserved
- names (Levenstein distance) - More and more strange names, perhaps invented
- patterns (.ly, .io) - But that gets crowded very fast
- composed names: "Diffie Hellman"
- 3-part composed names: Will that be seldom in 2020 when all 10-letter domains are taken?
- Even a small sentence, as long as it's unique enough for Google to identify it.
But it seems I'm not good at predictions: Companies keep recycling the same names, the domains expensive, and VCs don't like founders who didn't put enough thought in their brand.
Surprisingly, these both give useful results in Google. The Pages app is at the top, and the Numbers app is only four down (after "Number" on Wikipedia and a couple of results for the Numbers/Numb3rs TV show).
I suspect some hand-tweaking on Google's part.