I was just reading about X2.  It seems in X2, when you hit the magnifying glass, your view stays in the same position.
 
That may sound trivila to some people, but it also may be reason enough for me to upgrade.  Words cannot say how much I despise trying to zoom in on a wave (like to remove a pop) and then completely losing my place—especially when the place I need to be is not a particular bar but a particular tick.
 
 
Imagine if you were in Google maps or on your GPS and the Zoom button flew you from the street you needed in Fort Worth to somewhere in the Yukon.

If you're referring to the Timeline zoom, then yeah, it's a great feature IMHO.   So is the ability to zoom and then drag the timeline in a single motion without switching tools.

As many of us have said X2 is a refinement of X1. The features in X2 are by and large a further evolution that has many great improvements. Its hard to name one feature that is more impressive then others. They all as a whole make X2 a very nice upgrade.
 
I have found R-Mix for example very useful. I really like the auto zoom. I think its a really great version.  

I've gotten some use out of R-MIX as well.   I was able to minimize the levels for certain instruments and vocals in some live multi-track recordings, both active and bleed-through, where new versions of those tracks were recorded at home.   I probably could have done the same with EQ, more or less, but R-MIX did work fairly well in this application.    While I thought it might be a fun tool to have for experimentation, I didn't expect to get some real-world use out of it quite yet.   
 

Touch! I think touch is a lot of fun. It really opens up the kit of toys for experimentation!

Yes, the improved timeline zoom is the reason why I upgraded.

stevec
If you're referring to the Timeline zoom, then yeah, it's a great feature IMHO.   So is the ability to zoom and then drag the timeline in a single motion without switching tools.

Yes, when I first went to X2 I didn't realize how much I would like these features. Also the track auto-zoom.
 
And I think automation lanes are great. 

piano rolls / last touched.
god my life is sooo much easier now.

Since I've been working in X2 the thought of working in X1 or Sonar 8.5 again seems painful. X2 has a bunch of overall refinements that have really made it easier and more efficient to work on the music.

If I had to single out only one thing as helping the most it might be auto track zoom, but that's only one of many things.

piano rolls / last touched.
 
+1