I was in SoM beta for quite some time, and I personally am not thrilled about SoM's launch myself. Regardless, I think a lot of people will enjoy it (especially at first) but to me Turbine has ignored or worsened some major problems.

They chose to hang on to the legendary item and gear gating systems, regardless of the frequent strong negative feedback they've received in regard to both. In SoM they've attempted to soothe the worst problems with some small tweaks to both of these systems, but in the end they will turn out to be just as bad or worse than before. For example the new raid content is great, but it's kind of silly that it offers a downgrade in terms of gear sets from the first original Moria set that can be acquired from 6-mans. The new LI system is... strange at the least, requiring entirely new item XP to level up items at level 61 and above.

Mirkwood itself does provide a fairly sizable new area with great look and feel, and a pretty interesting backstory. However, it also seems that Turbine has taken a step backwards with quest design and progression in certain parts, almost frustratingly so at times. The skirmishes are a highlight, and are enjoyable even solo and provide decent rewards. The best part is that they scale by level, and so hopefully will provide new content to fill in some of the still-present level gaps in progression.