I am very much aware of the double-edge sword nature of macros, and therefore follow and aid their progress with much trepidation. The single thing that sold be was that macros by themselves already could replace a compiler phase, which did code reification (i.e. generate ASTs at run-time; something that's needed for LINQ like technologies). So in that sense, macros, if they arrive, would already have paid for themselves. Concerning possible misuse, I believe the best thing we can do is give an option to developers. So we plan to enable macro definitions only if a special import is present. Something like:

import language.macros

Of course that will not prevent misuse, but it will make it much easier to enforce policies, if someone desires that.