Just 8 hours into SH2, impressions -
1) It's one of the better-looking "fully-3D" PS2 RPG currently.
2) Music is much improved. The 1st experimented with more "foreign" and perhaps "original" styles, but remained so-so.
3) Improvements to the combat system are vast, making SH2 seem like coming from a totally different universe from the 1st. In fact, I find the new combo system makes it one of the most enjoyable combat system this generation of RPGs.
4) Map design is also greatly improved. Exploring dungeons and various locales is quite enjoyable.
5) Improved production quality all around, including story, setting, mood, voice-overs for characters, cinematic cutscenes, etc.
6) It has acquired a flavour of its own - a respectable accomplishment. Mixing seriousness and humour together very well, like the "Slayers", "Inuyasha", etc.
7) Fusion system is improved to make it less difficult and repetitive to acquire fusions. The 1st required the defeat of specific element-aligned enemies to earn soulenergy for that element. SH2 unifies all soulenery to be used for all fusions.
8) Judgement ring customization in the 1st was poor. Customizations are wasted once characters upgrade their weapons(I think, can't remember). Now characters' JRs remain with them regardless of the weapon and are also customizable, adding more interesting statistics to fiddle with.
One complaint:
Gamers may find themselves investing in fusion forms that aren't useful for various stretches of the game - for hours of play enemies which are vulnerable to the invested fusions just don't appear, while bosses that aren't do! The only way to be "sure" is to invest in all fusions in preparation for any encounters. However this will involve a lot of repetitive combat.
My solution is of course, to have the latest issue of Dengeki Playstation beside me so I know which fusion to invest in and when.
Hey, this really saves a lot of time and repetitive fighting.
Summary
Besides the one complaint, SH2 is shaping up to be an enjoyable experience so far. If this quality continues, I'll have to rate this title among the best RPGs this generation.