Helios is the simultaneous release of 39 Eclipse projects. In terms of statistics, the Helios release includes 33 million lines of code developed by about 500 Eclipse.org committers from 44 companies...You can read here and you will be impressed by the new Helios.
The best part for Linux users is Linux tools.
As Andrew Overholt says in the same article:
"The Linux Tools project also aims to increase the amount of Eclipse technology available in Linux distributions. We are working towards this goal by providing a build harness of the Eclipse SDK that is easy to consume for Linux distributions and already have a number of distribution consumers."I have not yet found the negative aspects from the Helios ...