Can I purchase this from developer today and download the program instead of order the CD and wait for it in the mail?
No, it's not possible to buy the application as a DOWNLOAD. The official website lists the product as being available only for physical delivery (aka box version). I have simulated a buying operation and there was nothing related to the download version of the program.
However, you can contact them because it's possible they'll propose an offer for the download version. You can use Live Service available from the following page: http://www.novadevelopment.com/support/customer_service/index.html