As usual take this information with a grain of salt.
Reddit user Megamanexe4 has become quite a person to pay attention to if you’re heavily invested in the Destiny scene which, statistically speaking, you are. The Reddit user has been successfully dropping leaked images of content ahead of time thanks to some Data Mining of the game.
According to Megamanexe4, the next Weekly Heroic and Nightfall will be featuring the Archon Priest. Nightfall strike will be at level 30 and Heroic Strike at 24, 28 and 30. The Nightfall strike will feature Epic, Nightfall, Arc, Solar and Void modifiers whereas the weekly Heroic however is only going to feature “heroic” and “void burn”.
Megamanexe4 has also leaked future (not necessarily next week) Xur stock listing which will include Crest of Alpha Lupi, Ruin Wings, Obsidian Mind, Apotheosis Veil, MIDA Multi-Tool and Dragon’s Breath. The information is only as good as its source, so it’s subject to change. Though for the most part it has been fairly accurate in the past.