This massive iPad would come in handy when trying to grow my new start up videography business. It would be used to edit video on the go and review my shots! I would definitely use the 'Pro' in this iPad!
I will be using it as a Christmas gift to my girlfriend... I was surprised when she said she wanted one, and she never splurges on herself, so this would be a home run for this little elf...
The company I work for just recently rolled out their BYOD program, so this would be the perfect device to be able to multitask at the office and have a considerable screen estate that will not slow me down.
If I win and being and amateur photographer I'll be using the iPad Pro mostly for photography purposes. I think it will be great to use it to edit and retouch pictures on the go using the the pen. Also the big screen and speakers will allow me to enjoy better training videos and with multi-touch practice at the same time.
I would use it for work. I do a lot of planning for layouts of audio and computer systems. This would make it easier to follow the prints and diagrams.