Tuna Eh, it's not quite that simple. Elementalist do have some strong advantages at certain level ranges. 1-16 in significantly in favor of Elementalist for example. They will out-level a necro in this range, with relative ease. Damage shields are potent, as is Pet-Chaining, and pet Empowerment buffs, bandages, Necro toolkit is far more versatile, but at least in the 1-40 game, Ele's are still robust/potent, despite some glaring issues.
I've heard "Necro pets are the same" a few times, but not really. They might ahve the same HP/AC/ATK, but the elementalist kit changes the math a bit, better heals, haste, pet always equipped with weapons for DW as opposed to sometimes equipped, damage shields, empowerment. Even if they are "The same" they are not "The same". Whatever mana effciency is lost on the Ele is made up in spades by Damage Shields.. the most efficient form of damage in the game, aside from pets themselves. At least until scaling issues arise and the DS math gets mucked. Not sure when that happens, it did not happen for me 1-25 run on Ele.
Necros are "Technically better" at solo then elementalist, but the way it plays out is not how you think. Similiar to EQ i'd imagine. Necros might be better equipped to solo dungeon crawl, or take down very hard targets out in the open. But they are not as potent in tight quarters, and while gameplay might look like a necro pulling yellows/reds the Elementalist will have killed 3 light blues in the same time, so XP/Hour, and Loot/Hour is "up in the air" between the two. There is something to be said for simple robustness, no song and dance required, you either can do the content or you can't. No FD and losing the pet to have to re-summon it, no root rotting, no fear kiting, just send and go or no.
In the last 2 weeks of Beta i played Necro to 12, then i played ele to 12, the ele was significantly easier/faster. I stopped playing necro at 12, and played ele to 25, then another ele to 15, then another ele to 12.
When it's all said and done, Elementalist will likely end up slightly ahead in the group game, but that's not guaranteed, if they never give us AE or COTH.
I still plan to EA start Elementalist, despite how busted they currently are.