I haven't been around these forums since forever ago so I'm a bit late responding to this thread. From what I can tell from my friends who still play MTG, it's still the only played CCG around if you're over 12 years old.
What makes a CCG interesting to me is the customization. You have from a few hundreds to thousands of options to put into your deck. And unfortunately they also figured they could cash in on some people's need to have stronger cards than their opponent. But honestly that's exactly what attracted some people to the hobby. I once spoke with a guy that admitted that if they printed a 20/20 artifact creature with haste that costs 1 and sold it for a ton of cash he wouldn't mind because he'd be one of the guys with that card.
Also, MTG was the first kid on the block and they did it right. Magic is to CCG what World of Warcraft is to MMO. It was the first to get it right (or first at all in MTG's case) and it grew into an extremely polished product over a long period of time. MTG has had at least 6 major revisions of their rulebook, to make them as clear and easy to understand as possible. They've had 30 to 40 expensions that they can pick from to create their base set. And somehow a new game has to beat that right off the bat. That's rather harsh.
Something else that helped MTG is that it's very theme neutral. Players represent Planewalkers, mages that can reshape reality, can do about anything and can go anywhere in a multiverse that could contains worlds from any fantasy or science fiction work. I think that a theme that can appeal to most anyone at all is one of it's biggest strength.
I don't think MTG will die, not for another 10 years at the very least. At worse they might slow down the rate at which they produce new sets in a few years but we'll see.
Now with that said LCG on the other hand are good and getting better. So far there's only one company that makes them (Fantasy Flight Games), but if anyone known of any CCG that you can purchase all the cards in preset packs please let me know. That's basically all that a LCG is. And what I mean by them getting better is that starting next cycle of packs, they'll contain 20 sets of cards (so 60 cards as these games also have a 3 of each limit) for 15$. Currently their packs had odd numbers, C'Thulhu for exemple had 2 copies of each card (so you had to purchase two packs to get a play set and you had one copy of each extra that went to waste unless you found someone to split a pack with).
The quality of the card design is good but the design teams are clearly smaller than MTG. As in, it's only one or two designers working on these products plus play testers. And thickness and feel of the cards is more akin to playing cards (standard cards used in poker, etc) than Magic cards. Time will tell if the quality of these will hold up long term.