Although that seems a long way into the future, its actually only 9 months.
You can read more about the post at An old friend comes of age. Joomla users and webmaster will have to carefully consider whether they want to migrate their site to 1.5.
Migrating from Joomla 1.0 to 1.5 can be a challenge for bigger sites, and its critical to make sure all the extensions you need are 1.5 ready.
I suspect that there will be a brisk business by developers/designers offering this service to parties that don’t have the time or expertise to manage it themselves.
Are you planning to migrate to 1.5?