If you have a Kobo e-reader, you can sync the articles to read them offline on an eInk display.

It keeps track of what you read.

It has more context when browsing, instead of just the website's title.

There's more to it.

I don't use it these days, but when I was heavily commuting on the London tube I used it a lot.

It downloads the bookmarked content, it allows you to organise it with tags and such, and archive it. And it's cross platform ( i can save an article on my computer and it will be downloaded on my phone).

I consider it more a distributed to-read list than a bookmark manager.

Pocket is an offline reader (and content reformatter), like instapaper, it's a rather different use case than bookmarks.

I don't bookmark articles I intend to read, but I do shove them in pocket, from where I can access them later then mark them as read.

It used to have text-to-speech functions. I even made lo-fi hip-hop type music using Pocket.