A few days back Sun offically announced they would be open sourcing Java under the GPL to applause from most of the industry. For a long time it was generally accepted that Sun would be fully open sourcing Java, the real question lay in exactly what license would be applied and how it would be undertaken. It turns out things will take about a year to be fully open sourced but even now the OpenJDK website is looking very promising.
From an end-user and developer perspective the GPL is by far the best consequence. As it is compatible with Linux we should be seeing Java making a bigger appearance within distributions. Currently all distributions have a means of installing Java but it is hardly mainstream but no doubt in the very near future we will start to see distributions appearing with a nicely packaged and easy to install Java stack. My guess is Ubuntu Server will be the first to take advantage of this new license given the close relationship they already seem to have with Sun. One thing I hope is a consequence of this release is better integration and support for servlet engines (i.e. Tomcat) within Apache. Personally I would love to see an Apache module that made deploying Java applications as simple as the current PHP modules. Sure JK is available for hooking Tomcat into Apache but anyone who has used it much will tell you that it is hardly straightforward and definitely not much fun compared to the easy life PHP has.
How this announcement effects other aspects of the Linux/Open Source world is hard to tell. David Berlind has an excellent post on how this news may effect the recent Novell/Microsoft patent deal especially considering when it comes to 'prior art' .Net and its runtime is a direct copy of Java. David Berlind writes some excellent articles and makes a good team with Dan Farber on the Between the Lines blog & podcast, David is often emotional with some left-field ideas but Dan balances this with a good dose of reality and industry skepticism.