Some observations:
It's a small sample size, because as folks have pointed out, not a lot of people have access to the PHB yet. So some of this can be taken with a grain of salt. I'll recreate the poll after it closes.
Wizards are looking popular with 13 votes. It's interesting that they are spread out among most of the schools, suggesting that the schools are mostly well thought out.
Paladins are also looking popular with 12 votes, and all Oaths are well represented.
Warlocks got 11 votes, with all the patrons and pacts represented, although the Fiend patron and Chain pact didn't get as many.
Fighters got 10 votes, with no one voting for Champion. I think Champion will appeal primarily to the Basic edition players. Interesting to see so many votes for Eldritch Knight.
Bards got 8 votes, quite a lot IMO.
Barbarians, Monks, and Rogues got 6. I was surprised to see Assassin getting none, although at least one person mentioned interest in it.
Sorcerers got 4. This doesn't surprise me, their write up sort of left me cold.
Clerics also got 4 responses. It's very telling that one of the more useful, and possibly powerful classes is one of the least popular.
Druids got 3 votes, all for Order of the Moon.
Zero votes for the ranger. Neither archetype has received a single vote so far out of 66 responses. That's surprising, but I have to admit, the ranger was the least interesting of all the classes to me. IMO it's because a spellcasting ranger just wasn't a popular design choice.
Threads like this one also suggest that the class is underpowered, at least on paper, but I doubt that's why it might be unpopular. I think it's just that this isn't a good representation of the archetype that people want.
That sort of logic maps well to my opinion of the other classes. The more popular ones have abilities that do seem to map well to the tropes and archetypes that are popular in fantasy.
Fully 1/3 of the responses so far are from DM's, not a surprise as ENworld is a fantastic resource for DM's.