1 -- Tick. Ivy Bridge is a die shrink of Sandy Bridge with a better integrated GPU and battery performance. If you're on a desktop with dedicated GPU(s), performance improvements between these platforms will be minimal. May have better overclocking potential, but the actual technology for non-mobile platforms isn't dramatically better.
2 -- Most likely yes.
And to answer the original question, if you're wanting a laptop, definitely wait. If you're building a desktop, there's little need to wait other than for a better deal on a last-generation CPU.