That's a bit of a difficult question to answer. I already run 5th edition for my players, in some form, so for me it's worth getting; I'm already predisposed toward buying it. The book has some beautiful artwork, and it provides a lot of details for playing this edition of the game. There are references peppered throughout of details and options one might find in a variety of campaign settings. If you think you might end up playing quite a bit of this edition of the game, then yes, it's very worth getting.
If you're unsure whether you'd be playing, then it would be best to take a look at the book at a bookstore or gaming shop and decide if you like what you read.
If you only ever play 3.5 or Pathfinder, or if you read the new PHB and don't like what it's offering, or if you simply has some other form of bias against it, I'd say no, don't get it.
Personally, I've been enjoying my time running the game, and I've made plenty of comments to that effect. Most of my friends who've checked out the game, both near to me and those I've simply met online, seem to also enjoy the system.
Many others, however, have preferences that don't align with any other edition of the game than what they are either already playing or which would provide whatever else they're looking for in a game, and for them it's ok to not like the new books. It's ok!
For me, I love Dungeons & Dragons, I always try to remain open-minded, and I've tried my hand at a fair variety of D&D editions and alternatives. This edition of the game aligns very closely to what I like about D&D, and so far, it allows a game to be as simple or complex to put together as I like.
For what it's worth, the PHB and other core books are still available to preorder on Amazon at ~$30, which is $20 less than the retail price.