This is to make people aware and inform about an ongoing effort to replace Indicators in Debian (most people know the concept from Ubuntu) by a more generically developed and actively maintained fork: Ayatana Indicators.
TL;DR;
In Debian, we will soon start sending out patches to SNI supporting applications via Debian's BTS (and upstream trackers, too, probably), that make the shift from Ubuntu AppIndicator (badly maintained in Debian) to Ayatana AppIndicator.
Status of the work being done is documented here: https://wiki.debian.org/Ayatana/IndicatorsTransition
Why Ayatana Indicators
The fork is currently pushed forward by the Debian and Ubuntu MATE packaging team.
The Indicators concept has originally been documented by Canonical, find your entry point in the readings here [1,2].
Some great work and achievement was done around Ubuntu Indicators by Canonical Ltd. and the Indicators concept has always been a special identifying feature of Ubuntu. Now with the switch to GNOMEv3, the future of Indicators in Ubuntu is uncertain. This is where Ayatana Indicators come in...
The main problem with Ubuntu Indicators today (and ever since) is (has been): they only work properly on Ubuntu, mostly because of one Ubuntu-specific patch against GTK-3 [3].
In Ayatana Indicators (speaking with my upstream hat on now), we are currently working on a re-implementation of the rendering part of the indicators (using GTK's popovers rather then menushells), so that it works on vanilla GTK-3.