Not much in terms of big changes, only small adjustments here and there. You might not have been there when they implemented the luxury tax, and you can now have 3 free decent players if you finish the new manager checklist. I think the basic arena is now slightly bigger, and they also implemented secondary staff and additional building to the arena. All of these help boost a particular area of training or revenue. It's quite expensive though so might not be very useful to you.
Other than that it's small changes to the game engine to make things like LI less efficient. Nothing drastic you'll get back in quite easily ;)
Training is still slow as hell too, nothing new there...
Welcome back!