Everyone should temper their expectations on a vaccine. While early signs on a few of them look good and with all of the resources/money that are being poured into finding one I'm faily optimistic there will be one (the scientists are all saying they are optimistic), but we're still in a "wait and see" how testing goes with large scale testing. All of the scientists are saying "Best case scenario, if we're lucky" there might be an approved vaccine by end of year/early next year. But up to now they have never been able to successfully create a vaccine for a coronavirus in the decades they have been trying. Also, the fastest a vaccine of any kind has ever made it to market has been 18 months (one) but most takes years and years (if ever).
Let's also consider on how long it will take to have enough quantity of a vaccine available for the full population at large. Sure they are starting production early on some of the most promising current vaccines so that once it's approved that there will be a lot out there from the start, but it's not going to be available to everyone from day 1. Front line workers, the elderly, the immunocompromised etc. will all be the first ones to have a vaccine available. I'm guessing it could be a good while longer until it's available to "healthy" regular folks who don't work in hospitals, schools, servicing the public etc.
It's good for some optimism but people should dial things back from expectations that there for sure will be a vaccine, by the end of the year, and that everyone will have access to it, and that everything will be back to normal by early next year.
Edit: My personal hope/optimism is that there will be a vaccine developed and approved perhaps by sometime early in 2021 (March-ish maybe?) and by the time it's available to all by the end of 2021. But also hoping that there are also good therapeutics found in the meantime as well that can also help with battling the virus for those who get it, so we can get park going experiences closer to what they once were sooner, rather than later.