Vendors have complained that customers take a very long time to adopt their latest releases, and now they are doing something about it - adapting.
Deploying new messaging servers and clients is time consuming and expensive and IT budgets have been extremely tight for the past two to three years. Where organizations once upgraded to new releases of email software every 12 to 18 months, today it is more like every three to five years - with deployment of new client software requiring the greatest time and effort.
IBM/Lotus have recognized this trend and started to adjust the major emphasis of their product development cycle between client and server enhancements with each alternating release. So for example the Notes/Domino 6.x releases contained mostly client-side enhancements and the upcoming 7.x releases will be largely focused on delivering server improvements.
This approach has been well received by customers and feels very natural. A messaging upgrade (particularly in a large organization...) is generally a staged effort starting with servers and working "downward" toward the clients. Alternating release schedules - coupled with excellent compatibility between releases - enable clients to upgrade with less disruption on a schedule that makes sense.
One Comment
I agree, having the ability to focus purely on the server piece, allows you to quickly take advantage of server improvements usually scalability or performance), without impacting your users.
It also gives you time to get your infrastructure in place, before making client side changes