help with laptop choice?

when should I buy my new laptop? My school provides laptops during the school year, but they take them away over the summer. I'm a photographer, and I use mine a lot to work with my pictures, and I'm definitely going to be doing a lot this summer. My parents said they'd buy me my college laptop now so I could use it over the summer, but I would probably just use the school one during the year. Should I do that, or would it be better to wait and get the most recently updated technology? Will the macbook, macbook pro, etc have changed that significantly from now until next spring to make it worth the wait?

The MBP's were just updated and if you don't have your own personnel computer no time
like now.

Tada.