If you have a non-production system you'd like to test on, and feel you can give good bug reports in the event of trouble, maybe you should give it a spin. But heed Alex's warning:
In addition to the 32-bit Live CD, you can also add emc2 to a 64-bit install by using the emc2-install.sh mentioned in the linked message. That version is even more experimental than the 32-bit version; Unfortunately, I see kernel crashes after 2 days to 2 weeks even when not running EMC2.Disclaimer
Before describing download and install procedures I would like to point out that at this point the packages have been tested by a semi-large number of people, and only a couple problems have been reported so far (on some hardware where it doesn't work at all). Therefore I do not encourage at this point to replace a working dapper install with the new hardy version. Dapper is still supported until 2009, and as long as it's supported we will be building emc2 packages for it.