Larry "Major Nelson" Hryb of Microsoft announced earlier in July that beta tester applications were open for the latest version of the Xbox Live dashboard. Hryb recently announced that applications are again open.

"The amount of interest we received in July for the 2012 Xbox Live Update Public Beta was so staggering that today we're announcing a second open call to subscribers to test out the beta program," Hryb said.

The previous registration period seemed to close as quickly as it was announced. Registrations for the second period currently still appear to be open, and an Engadget tipster claimed that 500,000 signs-ups are available on a first come, first served basis. Perhaps Microsoft raised the threshold for sign-ups, though there "is a high demand on the site right now" according Hryb.

To sign up for the beta, register here. A non-disclosure agreement (NDA) is required, which prohibits users from sharing information on the beta, despite photos of the updatesurfacing. Hyrb said users who break the NDA will be banned from future Xbox Live dashboard betas.

Xbox 360 consoles accepted into the program "should" remain compatible with non-beta Xbox 360s, according to Hyrb. A dashboard beta program in 2010, introducing the new Metro-esque user interface, disabled Xbox Live party chat with non-testers.

The new dashboard update includes features announced at E3 2012, notably Internet Explorer for Xbox. Voice search for "specific markets" is included, as well as the ability to pin tiles and favorite applications, enhanced "category search and discovery features," and software recommendations and ratings.

Microsoft refines the dashboard annually, with the move towards a Modern UI-esque interface in the New Xbox Experience. Whether Microsoft will revise the look again to be in-line with Windows 8 desktop, as the next-generation Xbox console launched, is unknown. However, the similarity of Windows Phone and Windows 8 indicates that Microsoft is developing consistency across its operating systems.

Registration for the dashboard betas usually last for short periods, so while registration is currently open, it could close again as early as this afternoon.