During the years building up to the release of Java SE 7 (and JDK 7), I appreciated (and blogged about more than once) Alex Miller's Java 7 page which he meticulously updated to reflect new articles and posts on Java SE 7 features and indicated features that were dropped from Java SE 7. We are now in 2014, the year in which we should see Java SE 8 formally released. The closest thing I've seen for Java SE 8 to what Alex did for Java SE 7/JDK 7 is Eugen Paraschiv's Java 8 page.
The Baeldung Java 8 page states that the page will be "updated with new resources as they’re created (and as I find them)." The page lists Java 8 features with with links to resources with more details on each feature and marks which features have been dropped from Java 8 (JSR 337).
Other online information on Java 8 that appears useful includes Oracle's Java SE Page, OpenJDK 8 documentation, Everything About Java 8, Java 8 Tutorials, Resources, Books and Examples to learn Lambdas, Stream API and Functional Interfaces, and The Java Source blog. It's also worth pointing out again that the Java Tutorial has been updated with many of the most significant Java SE 8 features (such as lambda expressions) already.