Wow, it's taken them long enough -- four months?! From what I'm reading into their announcement, though, it sounds as the new decoder will be able to read scripts encoded for older versions of Ioncube, so at least that should work.
At least that means we're just waiting for a final release of Ioncube, then. Once that's ready, there's nothing left keeping us from upgrading.
(Personally, what I'm most excited about is PHP 5.3's support for .user.ini files. They're like .htaccess files, except for PHP configuration. Having these available will mean that 99% of customers who are currently using custom PHP setups won't need to anymore.)