I am more than happy with Elite, yea the missions are a little shallow at the moment but Powerplay 'should' fix that. Imo, Elite should be played with a more sandbox approach then people are giving it. There is the risk of it adding the graph element as Neil is saying but even if that is the case, I think people need to remember that in essence, Elite is still unfinished too. If the powerplay doesn't work or people still are unhappy with, I can pretty much guarantee that FD will work on changing it or add more to get it right.
They just had a different approach (and much better in my opinion) in releasing their game. They focused on getting the base game in and how they want it, and then release improvements/modules piece by piece. They are excellent at listening to the community and judging their choices by it. By the time the Planetary landings and walking around in your ships etc are out, the game will be incredible. I am REALLY looking forward to Star Citizen myself, but I do think there will be a lot more problems early on in the games life than Elite had. A lot more. In the end though, I think they are different games and will coincide with each other quite happily.
Lastly, Elite will never be forgotten, it has too much of a following from the older generation of players etc.