I know I've been out of the loop for a few months, but I just had a brainwave I had to share.
What do people think of Future Sight on Alakazam?
Hang on there don't disregard it yet! Allow me to explain... by talking about Doom Desire and Jirachi.
I'm sure some of you remember when there was a fair bit of talk speculating about the usefulness of Doom Desire on Choice Specs Jirachi. While initially the mechanics of the move seem incredibly undesirable (it doesn't do anything until two turns later and your opponent KNOWS its coming), it presented some interesting possibilities when thought on more. The biggest idea was that it could force a "no win" situation for an opponent if played properly; After Doom Desire is used the user can switch to a new Pokemon that is checked by Pokemon that Doom Desire destroys. If the opponent dares to switch in their check, they'll lose a Pokemon to doom desire. If they don't though, that Pokemon gets a free turn.
Ultimately though the idea proved mostly impractical, due to three things: Too few Pokemon were threatened by Doom Desire, making trapping difficult,the sheer loss in opportunity cost of using a Choice Specs Jirachi when it has MUCH better things to be doing, and the fact that Choice Specs were necessary to get the damage output needed but otherwise pair horribly with Doom Desire's mechanics.
Which is where Future Sight and Alakazam come in. While Future Sight's Psychic typing isn't great, it is better than the Steel type Doom Desire. And unlike Jirachi, Alakazam always has a move slot to spare. The only moves Alakazam NEEDS are Psychic/Psyshock, Focus Blast and Shadow Ball. The fourth move has always been of far, far less importance and served a niche role. Well, here's a new niche role Alakazam can fill with that 4th move. And unlike Jirachi, it doesn't even need Choice Specs to pull it off due to its higher special attack and the better typing of Future Sight.
What Future sight does for Alakazam is that it gives it something useful to do on those turns when you KNOW an opponent is going to switch but you can't be sure what they're going to switch to. Rather than take a blind guess, you can throw up a future sight. From there you can play to "trap" the opponent. This doesn't necessarily mean that you need to get your opponent to send in a Pokemon that is OHKO'd by Future Sight; honestly there aren't a lot of those. However the extra damage caused by future sight can turn what is usually a solid check to a Pokemon on your team into a victim, since it does damage in ADDITION to whatever other attack you called that turn.
For example, say you get in your Alakazam on an opponent's Conkeldurr. You know they're going to switch out, but you don't know if they'll go to their Blissey or their Scizor. So you use Future Sight, and your opponent sends out their Blissey. You can then switch to your Double Dance Terrakion as Blissey does whatever. Your opponent is now in a pickle, because if they keep in Blissey you'll easily KO it, but if they switch to their Scizor the extra 38%-44% Future Sight will do will allow Scizor to be KO'd by Close Combat after it switches in. Indeed, Scizor is something of a best case scenario for them, resisting Future Sight; almost anything they switch in is sure to be destroyed by the combined might of two powerful attacks on the same turn. It's even better if you have SR or Spikes on the field, since that turns possible KOs into Guaranteed ones.
This could be avoided by your opponent by switching out Blissey in a blind double switch, but doing so against Alakazam is risky as hell since NOTHING likes switching into the right attack of Alakazam's. In short, it gives you a massive strategic edge that can allow you punch holes in your opponents team. Oh, and I know people will point out the fact that Dark types are immune to Future Sight as a flaw, but the only common Dark type in OU is Tyranitar who is destroyed by fighting moves, meaning it'll have a hard time switching in to whatever Pokemon you have out when Future Sight is ready to hit.
TL:DR
Future Sight works on Alakazam by threatening massive damage from two different attacks on the same turn. While the opponent can switch in a resist to the move, the added damage can still allow you to punch holes in the opponent's team, or force them into un-winnable situations.. Unlike Jirachi, Alakazam can afford the moveslot and use a less restricting item, making it able to perform its normal role as well.
So now, I'll just wait for people to tell me what I've missed, since I'm sure I've missed something.