I pay attention to MSRP very closely.
There will be very little people who will pay $199 on 2 year contract for this phone.
There will be even less who will pay $650 for this phone full price. Amazon must start to capture market share in order to demand this type of premium pricing
When Nokia entered the Windows Lumia market on ATT, they had the Lumia 900 that MSRP for $99 on 2 year contract/$450 MSRP
Even when Samsung was trying to gain traction in 2012 with all the USA carriers having the same Galaxy S3. The Galaxy S3 MSRP was $549 at ATT full price.
http://www.androidcentral.com/att-samsung-galaxy-s-iii-now-available-pre-order-shipping-june-18
Remember the Galaxy S and S2 models in the USA were a mess because each carrier had a slightly different design. Only starting with the S3 did USA finally have one model.
Once Samsung was able to capture market share, they increased the MSRP of the S4 to $629. Now they increase the S5 MSRP to what Apple commands, $649.
So Amazon has a huge uphill battle trying to sell this thing at $199/contract and $650 off contract.
I do think Amazon has a backup plan. If they lower the price due to poor sales, they will make it up to current Fire Phone owners by giving them $100 Amazon credit. I firmly believe this will be Amazon's backup plan if they decide they have to reduce the price.
Remember when Apple gave customers $100 Apple credit when the original iPhone was lowered from $599 to $399. Apple gave people (including me) $100 credit.
That will be Amazon's backup plan.