Right, ok, erm, ok..
Is it worth playing? Yes. It certainly had me feeling the same sort of way I did when I played Flower for the first time. Which I admit isn't exactly a good description, but if you got a certain, shall we say sense of calm/wonder/emotional attachment of some description with Flower (especially on the last level), then you'll probably feel that here.
Visually, it's possibly more gorgeous than you might realise if you've only seen screenshots.
At points I lost track of the fact I was using a controller. That might sound odd, but given you only really need 1 analogue stick and 2 buttons, there's nothing to really learn, and therefore nothing to forget. You just get absorbed with what is going on in front of you.
Reviews have put it at 2 to 2.5 hours to play through it. I just timed it at 1 hour 40 minutes. That's not a lot of game time for £10. Is it worth it? In my opinion, yes. Your mileage may vary. It's not often (if ever) these days that I'd say sub 2 hours for a tenner is worth it, but I think this is. It's one of those games you should play - though I don't want to overhype it. £6.99 would have been a better price point, but I certainly don't feel cheated at £9.99.
Looking at the trophy list afterwards, there are a few things to discover and a few tasks to aim for on a replay or two.
What I would say is that if you do play it, put a couple of uninterrupted hours aside for your first time through, so you can just relax and enjoy it. I think that's the most calm I've felt playing a game since Flower, even though it's a very different game.
Finally, while playing, I was just absorbed enough that when the first trophy popped up, the "pling" sound actually made me jump...