I'll get the one burning question I'm sure a lot of people out of the way first.  The game is free to play, and the premium content will thus far be coming in the way of perfectly normal items such as more character slots, extra storage, and aesthetic items.  It will also gate your access to things like opening up a shop or just trading in general (I don't even...).  There might be other things, but I'm not aware of them in game at the moment.
 
Edit: Timed license stuff like the "my room" and "trading" licenses come in 30, 90, or 120 days tiers, and for trading licenses specifically, costs 10, 20, or 30 Arks Cash respectively.  I don't quite remember for other stuff.  I'll bet that that translates to 100 yen / 1 USD per 10 AC.  Of course, this is the closed beta pricing, so it might still be subject to change. 

Feel free to ask me questions about mechanics you're interested in.  But I won't be able to tell you if it's better/worse than the first PSO considering my experience with that game was largely based on watching another friend play it during middle school

Is it awesome?

Is it fun?

since you asked, here's my post from another thread:

Is it awesome?

Is it fun?

since you asked, here's my post from another thread:

Does the character creator let you walk around and compare your height to other characters such as NPCs before finalizing your character?

It bugs me to make a character that is way shorter/taller than I had expected. (since it's not like I'd have any way to know) (and other features such like size compared to NPCs and how ridiculous your character/outfit looks when running) It's a seriously big problem with the Phantasy Star titles. Especially when you have to sit through a ton of story before and after every attempt at making a character.

I should note the pricing of the premium stuff as well.  Skipped my mind when I made the thread.  License stuff like the "my room" and "trading" license comes in 30, 90, or 120 days so far, and for trading specifically, costs 10, 20, or 30 Arks Cash.  I don't quite remember for other stuff.  I'll bet that that translates to 100 yen / 1 USD per 10 AC.  Of course, this is the closed beta pricing, so it might still be subject to change.

How similar is it to the first PSO or is it more like a modern MMO?

How similar is it to the first PSO or is it more like a modern MMO?