Personally I preferred it when the LMB selected, but did not move.
I agree that LMB move + select is the more intuitive method (particularly since that's how XCOM games worked). However, probably the most common way for one of my soldiers to die needlessly in UFO was through moving, when I meant to select.
Say your team is split between two areas of cover, and you've currently selected a soldier in one of these areas. Now you want to select a particular guy in the other area, so you go to select him with the LMB. Most of the time you'll click the guy correctly, but occasionally you won't [you'll click an adjacent square]. Perhaps that'll be 2% of the time, perhaps 0.1% of the time - but eventually it'll happen.
At this point the soldier you had previously selected (and carefully positioned in cover) goes dashing out into the open - often to his death.
When I played the 0.12 beta, I took a few minutes to get used to the RMB move, but I got used to it soon enough. Once I had, I was pleased to note that I could happily select any of my soldiers without worrying about their running across the map, or my needing to be careful to avoid this.
LMB moving makes this an issue again. It's not a big deal, but I definitely think it was better beforehand.
I know that it's quite possible to avoid the above issue, so long as you're careful - but as a player, I don't want to be consciously thinking about the user interface at all. With RMB moving, I can comfortably forget about it and play; with LMB moving I either need to be careful, or to use the buttons rather than click selection. That's not ideal.