One other factor that was important to me was eye relief. If you have longish lashes, you'll most certainly be annoyed if you have to bury your eyes into the glass and have lash rub. Long eye relief, while not essential to the view, can make or break the pleasure of a fine pair of binoculars.
My personal preference is 8 power. It give wide angle of view and is easily hand holdable. If you want more durable and perhaps water resistant, go with a roof prism. They'll cost a bit more than porro prism but you might like them best.
I use the fine Nikon 8x32 Superior E porros that are as good as they come. They're certainly not cheap though, but they will last a lifetime.
Here's a great site for reviews.
http://www.betterviewdesired.com/
Larry