Thanks for the info Prodo123
If the base 13" model can deal with my files appropriately right now (300-500MB photoshop cs5 is what my current MBP can't cope with) then I am probably in a position where I should go ahead as any waiting will also slow down my productivity. I've always bought at the start of product cycles though and I know if a new one comes next month, I will be kind of disappointed.
The base 13" model would be fine. Only thing i would recommend is maybe upgrading to 8gb since it is dirt cheap. Even your current one might be ok if you max out the memory.