*Nu-uh! It's 3 mana to draw 2 cards!*
No, the first card you draw is the card you would have drawn anyway if you hadn't drawn Arcane Intellect (which does nothing by itself). It's 3 mana for 1 card!
Virtually any other card that let's you draw is better than Arcane Intellect because that card also does something else.
Just to compare:
3 mana: Arcane Intellect - draw one card (the other card is one you would have drawn anyway)
3 mana: Fan of Knives - draw one card and do one damage to all enemy minions
3 mana: Far Sight - draw one card and it costs 3 less mana
2 mana: Loot Hoarder - draw one card when your new 2/1 minion dies
2 mana: Novice Engineer - draw one card and you get a 1/1 minion
2 mana: Shiv - draw a card and deal 1 damage to anything
1 mana: Flare - draw a card, all minions lose stealth, and all enemy secrets are destroyed
Anything is better than Arcane Intellect.