If one waited for what's new out around the corner, then one wouldn't end up making a purchase at all !
With not knowing what the new iPhone will look like aesthetically, and what will defiantly be under its hood I can only comment that the iPhone 4 and 4s ticks my boxes.
If you wait and don't end up being taken by the next iPhone you can always fall back on the 4s or indeed another manufacturers cellphone.
we're not talking about waiting 3 or 4 months...we are talking about 3-4 weeks....anyone with a brain would wait.