Here's a first beta version of Sweet Home 3D 3.7 bundled with Java 7 (74 MB).
It should work under Mac OS X 10.6 to 10.8 (only 64 bits processor are supported under Mac OS X 10.6).

Note the following known bugs:
- the top and the bottom of toolbar buttons are missing,
- the top of titled sub panels in dialog is too small,
- if the menu bar appears as empty when a document is opened, deactivate / reactivate the program to make it appear again (or open / close any dialog in the program),
- no default menu is displayed when all Sweet Home 3D windows are closed,
- there's no antialiasing in the 3D view.
The 4 first ones are bugs in Java 7 and the last one is due to current version of Java 3D 1.6 which is not finalized yet.

[Note: on 12/18/2012, this beta version was replaced by a new one based on Sweet Home 3D 3.8 Beta]