First of all, welcome!
Warren Buffett recently turned 78. He is one of those fortunate souls who loves his work; in the past he's referred to it as "tap dancing" to work every day. He's truly a blessed man to love his work AND be so good at it. There are few I envy more in this world than those who truly love their work. If I really loved what I did and had at least a little input into my working hours and conditions, I'm not sure I'd ever want to retire. But in the real world, as things are now, I'm pushing as hard as I can!
My personal feeling (not yet retired; I'm 43) is that if you have to question whether you're ready to know how to spend your time, you're not ready to retire. Just the same, it's never too early to configure your finances to enable it if you want to retire. One of the common terms you may hear is "FIRE" -- which stands for "financially independent - early retired". In reality, the FI part is the important part, because that enables the RE. (You can have FI without RE, but you can't securely RE without FI.)
If you're pretty settled in financially, then by all means start pursuing your dream! I'm not saying retire yet, but start dipping your feet into what you want to be doing -- whether that's reading books and being a critic (even if just on your own blog) and perhaps writing something of your own, if you have the energy to do that AND your job, it could be the segue from what you HAVE to do to what you WANT to do.
You have nine years between now and 50. And if your finances are in good order -- solid income, little or no debt, cash in the bank and solid retirement savings -- I'd encourage you to start baby steps toward what you want to do today! Someone who writes (and gets paid for it) is not retired... just self-employed! But if you're doing it as a labor of love, you can get the best of both worlds... "feeling" retired (working on your schedule, doing something you love) AND getting paid for it.
In all honesty, I wish I knew something I had a passion for that I could just start doing tomorrow without jeopardizing my current j*b... until what I wanted to do was successful enough that I could tell 'em to take the job and shove it.