Ok, I love horse racing so I think I can carry this metaphor far. Symbian used to race in stakes races(smart phones) but has gotten very old and is now relegated to cheap claiming races and can no longer earn more than it costs for stable space, feed and vet bills. It's time to retire her and let her become a riding pony for awhile, then put her out to pasture. WP7 is a 2-year-old who hasn't won its first maiden race yet but is showing good early speed and has just been claimed by an owner who's pairing her with one of the world's top trainers. The horse also has a superb pedigree/genes. Once the horse's few problems are ironed out she stands to be a formidible competitor on the track.