Instead of planning for a 3.0 release, GNOME is opting for a gradual, piece by piece updating that will culminate in a 2.30 release. The change in version numbers is significant: It indicates that, unlike with the KDE 4 series, there will be no major break with past releases. This philosophy was obvious long before it became official last summer, and has the obvious advantage of not alienating users.
In my opinion, despite Gnome's incremental approach, they are still highly successive in alienating their users.
"Atomic batteries to power, turbines to speed." -- Robin, The Boy Wonder