The end of June saw the annual arrival of the Eclipse release train, updating the current version to 4.5.0, code named Mars. As Dart Studio is basically a re-branded version of the Eclipse platform it would seem appropriate to update this too, so an updated platform release, 22.214.171.124, is now available from SourceForge.
The Dart SDK was also recently updated to 1.11.0 and can be downloaded from the Dart project website. However, the Eclipse plugin has yet to be updated (it's currently at 1.10.1) so there is no 1.11.0 release of Dart Studio.
If you can't wait and want to build an updated version of Dart Studio based on the latest Eclipse release just follow these instructions substituting the Dart Studio platform in place the official Eclipse platform in step 1.
Alternatively, the current Dart Studio release can be easily upgraded by replacing the 'dart-sdk' and 'dartium' directories with the latest releases. Unless there is some new Eclipse feature you can't live without this is probably the simplest option.