Thinking about this some more - I wonder if there is anyone who would prefer a later Jetty6 release prior to the Jetty7 one?
If so, we could do a stepwise upgrade from 6.1.21 to the latest Jetty6 (6.1.24) under say 2.0.6-SNAPSHOT prior to committing the jetty 7 changes under a 2.1.0-SNAPSHOT.
Obviously this is something of a half-solution - since we're still making an actual cutover point using this approach, albeit at the "current latest Jetty6" version. If anyone had longer term interests in staying on Jetty6, we'd need to figure a way to have parallel options e.g. move the current code to a jetty6 package for those wanting that version.
I doubt it's much of an issue - just something to consider