Possibly. I dont think it will include a full update on all the deities. THat would be ridiculously long. and Im still not convinced until I see it on the page that we will get any 'new' ones. I do think the update will simply be on those deities listed in the PHB (just obviously a couple of paragraphs on each)

(Also Azuth IS listed in the PHB, just under Auril).

I would like to see some expansion for the Demihuman races though which is where I think there needs to be some more (perhaps 2-3 more for each demihuman race). A good example with the Underdark focus might of been Shevarash (the Elven Deity obsessed with revenge, loss and Hatred of the Drow). With this season having a core focus on the Underdark and to some extent the Drow.. probably would of been an apt god to include)

Although of course the Elemental Gods of previous editions: Grumbar, Kossuth and so on would of been great for the EE season.