The phones in the image are Sprint's first Android device, the HTC Hero from 2010, a couple of feature phones and the craptastic Samsung Intercept, none which are very attractive BYOD phones. But, according to the dealer, the program will actually be available with 15 "current" handsets initially, with more phones being added over time. Several Sprint MVNOs including PrePaYd and EcoMobile are already activating most Sprint phones except iPhones and LTE devices. I suspect the Boost program will have the same restrictions.
The fine print at the bottom of the scan reads;
"IMPORTANT NOTICE: Activation may require payment of an activation fee. Only select non-Boost branded or configured devices are eligible for activation. Service limitations: Only voice data and SMS messaging services are available when activated on Boost, other services including but not limited to MMS and/or other non-Boost specific or configured applications may not function or be available. Other restrictions and exclusions may apply. See store representative or in-store materials for details."
In my experience with BYOD'ed Sprint handsets on MVNOs, MMS doesn't work out of the box but is pretty easy to fix on Android phones and some feature phones. Also on Sprint Android phones, Visual Voice mail does work but most other Sprint branded apps like Sprint ID and NASCAR do not.
Source XDA-Developers via Android Authority