Here’s a nifty gallery of comparison shots from TOS and TOS:Remastered.
I have watched (or at least fast-forwarded via TiVo to check out the new shots) several of the TOS:R episodes and, on balance, they have been quite nice. The only downside to the project, it seems to me, is that they are doing the remastering as they go, so there is something of a learning curve involved. Also it means that sometimes they can’t do as much as one might like.
I will say that the into shots from “Where No Man has Gone Before” as well as the galactic barrier shots were quite impressive.
Also, the “Corbomite Manuever” (which had a number of f/x shots) was noteworthy. Below is the effect reel. Note, for example, the reflection of the probe on the hull of the Enterprise at about :52.
More comparison shots can be found at Trekmovie.
Also worth checking out: the promo for “Journey to Babel.”