To be honest I haven't seen a huge amount of difference visually, though dx10 I only ran for like 5 minutes as I rolled a runekeeper to start and there appears to be a large bug where as soon as you use the fire spell they have the fps dips from solid 60fps down to 3fps for the duration, its a joke, turn dx10 off and its fine. As far as I could tell fine on everything else except that spell. hopefully something the patch would fix.
I believe the normal update sans Moria content is pretty hefty so would assume it has the graphical updates in, 3gigs or so in total and I believe you get the Eregion region but no leveling and no rune keeper or warden, the later seemed very fun to play up to lvl 15, Rune keeper seemed quite dull to me though its dps is supposed to only really pick up lvl 15-20 onwards.
THing is, its only £15ish and the subscription covers both so won't really cost you any extra, or less to get it now. Not sure if its available either but the lifetime subscription was £120 when you bought Moria, and £150 usually, considering theres several years more content to come I figured it was fairly cheap one off payment and I can come back in for new content whenever I like.
Moria is good, and bad, unfortunately I personally think its a tad too easy. I prefer solo'ing purely because if you ran around anything other than instances with 6 men it would be laughably easy. Solo theres almost nothing I've come across thats hard, one time solo'ing 14-15k elites is perfectly possible and thats almost as tough as it gets non instanced.
The content, although taking a while to get through, isn't too good, it all looks great and many of the story instances have been fun but to much of the story is the same in each book so far. To much in every area collecting the same crap from ridiculous locations for the same task. Some bright spark will say, thats an MMO for you, but this is rather more painfully similar in the various area's of Moria. dissappointed that whatever the place the other side of Moria is called is really very easy to get to, and theres smeg all there.
The other thing is, I don't feel hugely different at 58, than I did at 50, hunters get almost smeg all in terms of new stuff, basically one semi useful attack, a daze, and thats it. after 8 levels i still have most of my original armour which simply hasn't been outmatched so far, my morale/power are very similar to what they were, the attacking style/rotation is the same, enemies haven't vastly gained in power, they jumped from circa 3k moral at lvl 50 to circa 4k morale at lvl 51-52 and haven't really moved from there. This was always a problem with the original aswell, at various arbitrary levels all enemies above a certain level got a ridiculous bump in attacking power, morale, power and armour, etc, while you've only gone up one level and it goes from easy to stupidly hard. Theres no relatively good scaling across mob's levels, while at the other end of the scale say here, a lvl 52 mob is as hard to beat as a lvl 58 mob with similar weapons, damage output and morale with you doing similar damage to both mobs, it feels odd to say the least.
its still fun to play, I just, when I look back at all the questing, book work, stuff i've killed and scaling of difficulty in moria, scaling of mobs and my character, very little has come of all this effort. THe same change, from 40-50 previously yeilded far larger changes in mob's, story, zones, and character increased in everything far more than these 10 levels.