SLAX version 5.1.4, which was just released days ago, now has the latest and fresh KOffice 1.5. For those who do not know yet, SLAX is a Slackware-based Live CD. So download and try it if you want to see KOffice 1.5 in action without the need to install anything.
Note that due to space constraint (typical ISO only as large as 200 MB), only KWord, KSpread, and KPresenter are available.