Disapointment is an understatement to this whole TB to FW situation. As a lifelong Apple supporter and pro user, I am extremely unhappy. Lets be clear to what is going on:
1. Apple released rMBP geared mostly to Pro users in it's max configuration (my case - 2.7GHz 16 GB RAM)
2. Decided to eliminate the main and in almost all cases only bus used for periferal devices - FW, in use since late ninghtees.
3. Released workaround - adopter bridging new and old bus technology - TB to FW.
4. Adapter is released after we all invested close to $ 4K in new rMBP and as always supported Apple, with blind fate. Trusting, things will work out since they promissed adapter is on the way, not a big deal...
5. Than to realise that adapter is in majority of cases useless since Apple decided to brake its own standard for FW, the very standard Apple owns??? 7 W max power was minimum by Apple's own standard for FW, that states 7 - 30 W min to max available power. Since all devices were developed under that standard, conclusion is that Apple threw us all under the bus by tricking us into investing to the new rMBP, that some of us cannot use at all in the fashion we did before.
With $ 50K invested in photo digital back, that is essentially rendered into useless brick, if used with rMBP for location photography, I am very disappointed.