Before you hurry off and give Amazon 10 of your hard-earned dollars every month, there are a few things to keep in mind.
First, you need to do the math. If you currently spend less than $10 a month on books, it probably isn't worth it. Having access to over 600,000 titles won't make you a reader.
Second, access isn't ownership. With Kindle Unlimited, Spotify or Netflix you are paying for access to content for a specified amount of time. Once you stop paying, you lose access. Unlike physical books, you won't be able to pass your personal library on to future generations.
Third, Kindle Unlimited does have competitors. If you're interested in a subscription service like this, you should do some research. Caleb Greene mentioned the three below on Twitter today. I've taken a quick look, and they all seem to have something to offer. If you find another service that you think people should check out before choosing, please mention it in the comments.
Sidenote: Although Kindle Unlimited does include a library of audiobooks, it is still quite small. For those of you who prefer audiobooks, I would check out Audible.com (which is also owned by Amazon). I've had a subscription off-and-on for the last 5 years. The size of the library is impressively large, and I find that 1 audiobook a month is plenty.
Header image from Australian National University