You may remember a few months ago that the 5GB free 'personal document' storage was combined with the 5GB free 'cloud storage', so the total is now 10GB total per amazon account (with free photo storage for Prime members).
To manage this storage, you need to go to
www.amazon.com/clouddrive and login there. You'll see all the personal documents listed and downloadable, and under the 'Hello, X' dropdown menu there's a Manage Your Account link to see what you are using of this 10Gb (or whatever you have subscribed for).
So no, there is still a limit, but depending on how you were using it, you may have more for your personal documents now.
I would really like to see the 50GB Send To Kindle limit go away. One can of course upload larger files to Cloud storage but those don't get integrated with your Kindle library.