I actually think the previews I saw at the theatre were pretty funny. Greta Gerwig is playing the Liza Minnelli role, her name is Naomi in this version. I imagine Jennifer Garner's might have been beefed up in this adaptation, which I think is a smart move (why cast an A-lister in a role owned by Liza?). I wasn't a fan when I heard about it, but the previews have me somewhat convinced to at least give the movie a chance. We'll see how it turns out.
Interestingly enough, the John Gielgud role was re-written to be a female in the hopes that Meryl Streep would take the part but from what I read she turned it down after they made an offer. Helen Mirren looks pretty funny in it though.
"Some people can thrive and bloom living life in a living room, that's perfect for some people of one hundred and five. But I at least gotta try, when I think of all the sights that I gotta see, all the places I gotta play, all the things that I gotta be at"