I think when it comes to Satellite imagery Google Earth has taken the lead. I used to use it to find shortcuts when I hauled gas, but the photos always seemed outdated. I've used Google Maps & Ted's Satellite (Bing Maps) since I've been cleaning roofs, but I've always been leery of their "freshness." I just looked up my house on Google Earth and the photo is less than 6 months old. We got a hottub last year & it's on there, but the cover is on the pool and we didn't close the pool down until late Sept./early Oct. I had prettymuch quit using Google Earth but it appears to be updating as we go along. I guess it's a tool worth stickin' back in the old toolbox.
I have to use both. I prefer Bing because of the birds eye view. Sometimes that feature doesn't work on some locations so I go to google. The last time I looked up my house on google my dog that was put down two years ago was still lying comfortably in the back yard. I think they refresh your hot/pool pictures more than my boring back yard!
Google earth has updated my location also. I have used bing maps but agree some places won't show up, where google earth always does, but some location can be old?
I guess just a matter of what works best for your location.