well, first of all, when they "Tablet" they don't mean an Ipad or something like that, they mean pen tablet, which is a pad with a pen that picks up like a mouse, but with pressure, angle, and tilt sensitivity.
how does it benefit? well, it's fucking hell to try to get good at digital painting with a mouse, with the tablet it's like drawing on paper, not exactly the same, but simulates it pretty well.
it gives you the feel of pencil on paper. it's so much easier that you'll naturally be used to using it in a couple weeks time ( only thing that takes practice is drawing with your head up, for me anyways) it's really a great tool and i completely recommend buying one for SURE.
You get a good one. Like a Wacom Intuos brand. And you're gonna fall in love. A tablet for a digital artist is as essential a tool as a paint brush to a painter. As for what it does for Photoshop specifically, a standard tablet uses pressure sensitivity. Meaning how hard you press with the pen effects what you do on the screen. Additionally, the newer models (paired with the newer versions of Photoshop) use tilt sensitivity, so which way you tilt the pen effects the outcome, just like a real brush. Along with programmable buttons on the tablet itself and an Ipod-like touch ring that itself is programmable (you can set it to zoom in and out or adjust the brush size), it really streamlines your workflow.
The tablet is an input device that has been designed to behave more like a pencil (or paint brush) than a mouse. So it allows you to enjoy all the benefits of digital work (saved files, undo, copy paste etc.) and it will hold you back less than a mouse would.
However, you have to be willing to learn how to use it. It's like learning to use roller skates instead of sneakers. sneakers are much easier to use but roller skates allow you to be much faster and more graceful.
Also it does not automatically increase a person's artistic ability so you still have to learn all the fundamentals of anatomy, perspective, composition, color etc. I mention that as a general note and not a commentary on your particular skill level.
"Also it does not automatically increase a person's artistic ability so you still have to learn all the fundamentals of anatomy, perspective, composition, color etc. I mention that as a general note and not a commentary on your particular skill level."
Tablets are really useful because they've got the pressure sensitivity and a similar feel to pen-and-paper work, which makes it feel more natural. It's really the pressure sensitivity that's the big thing, because with a mouse, you'd have to spend so much time messing with opacity and such, and even then, your strokes would always be a uniform size (unless you did something with the settings that changed that...? Though I haven't found a way to do that yet; not sure if it's possible). It just makes the traditional-to-digital transition easier, in my opinion, by removing the unnaturalness of trying to use a mouse to paint.