Lots of people get into too much magnification because, like most of us, at one time or another, have gotten sucked up the "more is better" pipe. Magnification choice is largely personal and you will see two very definite camps for the 7-8x and another for the 10-12x. Personally I have a 7x and 10x combo I use, so there is room for both. If the gods decreed I could only have one, I'd take the 7x36 (mine's a ZEN ED 2).
There's a couple of things that happen with lower magnification. One is that the shake is minimized with decrease in magnification. You will see a LOT more with a clear, steady 7x image than a 10-12x wobbling around a lot. You won't get as tired either, and you will have a lot less eye strain at the end of the day. Then there is the issue of heat mirage. The effects are magnified with magnification and times out in the Eastern Oregon Desert, I have been able to use the 7's and the 10's got left in the truck. Image quality is usually easier to get right with lesser magnification (but higher ranges are getting batter, especially in the lower price ranges). Another thing about a 7x binocular is that the depth of focus is another thing that increases with DECREASE in magnification. Just means there is a lot more field in focus for and aft of the target and depth perception can increase dramatically in a 7x. Personally I could not tell you if a binocular was 7x or 8x if it was not marked. Just not enough difference to tell about, this is for me anyway, the side effect of depth perception (I think).
On the other hand 10x is 20% more magnification than 8x. There are lots of people who can take full advantage of that and they should stick with what works.
Basically, don't worry much about loosing too much magnification at 7x.
