I'd say it has changed quite a bit since '05!
There are some new textures and character models, new areas to explore.
The graphics (or graphic style) haven't changed too much, but the Crystalspace engine (rendering) has a lot more capabilities ready to be used by PS in the future.
The engine has improved a lot and many new features are being added or revised and improved.
There is much more settings content, more quests, more money and experience from them (the quest system is under rework, possibly for next release for menu-driven dialogue mostly).
There are now 2 servers! One for RP the other for Non-RP, and you can have (separate) accounts for both.
Of course, there are many more bugs!

Be patient, take your time and you'll do fine.