1. Simplify the product line even make it consistent across carriers. Apple seems to have been able to do that. Just had another local user ditch their HTC Evo for an iPhone same carrier.
2. Rebrand is it and HTC _____ or a Droid _____. If the consumer doesn't know or care they won't on the next purchase either.
3. Customer support and customer experience. If it's bad don't expect them to come back.