I enyoyed, both, the film and the book. It's an interesting variation on the time travel theme. I think "the Love" comes out better in the film.
Audrey Niffenegger introduces the first chapter with a quote from the Duino Elegies by Rainer Maria Rilke:
'...because truly being here is so much; because everything here
apparently needs us, this fleeting world....Us, the most fleeting of all.'
'...Ah, but what can we take along into that other realm?....
The long experience of love, - just what is wholly unsayable.'
This, for me, sums up the book very well. It's a very good piece of writing in my opinion.