Can I download TurboTax if I bought the CD?

For those of us who prefer physical media to digital downloads, a question arises: "If I purchased the TurboTax software on CD, will I still be able to download it digitally? The reason I ask is that I often find digital downloads more convenient for accessing and updating software. While I appreciate having the physical CD as a backup, it would be great to have the option to download the latest version directly to my computer. Does TurboTax offer this flexibility for those who initially purchased via CD, or is the CD the sole means of installation and updates?