To me, Flatt's proposal for Racket2 smells more like adding tools to better facilitate infix languages than depricating S-expressions. Given Racket's pedagogical mission, it looks more like a move toward migrating the HtDP series of languages (Beginning Student, Intermediate Student, Intermediate Student with Lambda, and Advanced Student) to infix syntax than anything else. Not really the end of the world or a big change to the larger Racket community. Just another extension of an ecosystem that remains s-expression based despite Algol and Datalog shipping in the box. It's hard to see Flatt's work porting Racket to Chez Scheme as a prelude to abandoning Scheme as the basis for the Racket ecosystem.

On the other hand, the reality is that Racket's syntax makes for an uphill fight when it comes to adopting the HtDP curriculum. Anyway #lang racket syntax is just sugar on the more important concepts in the HtDP methodology. The HtDP engineering principles are matter much more than which language is used at the top level.