"New edition of 13th Age"
Perks up
"Backwards compatible"
Perks down
I feel this deserves elaboration.
I'm looking forward to this. I ran a lot of 13th Age at one point and love it, but I also have a medley of minor grievances which ultimately added up to why I don't run the game anymore....which boil down to the following:
Icons - the icon influence needs a cleaner approach that doesn't overwhelm the GM with loads of encumbering improv (maybe a sliding scale of "level of influence" the icons exhibit). The current system can lead to a table full of positive and negative consequences the GM has to deal with, especially overwhelming if you have a big table and lots of lucky die rolls from players. I think almost everyone I know has had to house rule this to keep it under control. (For those who don't know, each PC has a set of favored, neutral or opposed icons who have a stake in their future; at the start of each session you roll dice and see if there's a chance of a positive or negative interaction that may take place during the night's session. This can get messy, fast.)
Languages, Vision - the game de-emphasizes the need for rules on vision and variable languages, leaving this to the adjudication of the game table. However, this stuff is easier to include and then let people ignore it than it is to leave it out and force people to make stuff up and add it back in. For me, knowing how well a given character can see in the dark and what languages they know have always been pretty important to my games. Providing scaled levels of rules support would be welcome.
One Unique Thing - more guidance on this would be helpful; although I didn't generally ever see issue with it, it was not uncommon for players to find weird ways to abuse the concept.
Skills - The free-form skill system is fine, but its the kind of skill system made by someone who doesn't want skills in the game and I am not that person, so a bit more structure would be welcome. I suspect it won't change, though, but that's not a deal breaker; I'd just be happy even with a sample skill list for GMs who want narrative consistency or players who lack imagination/make poor choices.
Ability Descriptors - In the current edition a lot of powers have zero ability descriptors. Even D&D 4E, the spiritual predecessor to 13th Age, included some sort of descriptive text. I know the idea in 13th Age is for players to make it up, but I encountered many gamers at my table for whom that was a more difficult task than it needed to be, and even some modest descriptors of what an ability or spell might look like in use would have helped them out.
In terms of backwards compatibility I take that to mean that Pelgrane Press does not likely want to monkey with the core mechanical chassis of the game, and also does not want to invalidate all their unsold back catalog of books. This is fine, totally fine. It could be a new edition in the same way AD&D 1st edition upgraded to AD&D 2nd Edition while remaining backwards compatible, and I think that would be totally cool.