The IF Comp is now over — full results and stat breakdown here — and a number of authors have been posting post-mortems and notes about their thoughts while writing. I love reading these things, as they’re often revealing insights into people’s processes.
They are, of course, spoilery by their nature, so read with care.
Coloratura (and see also earlier posts for details on specific aspects of the design)
Solarium
Moquette, plus a second post about technical features
Machine of Death
Threediopolis
Tex Bonaventure (specifically the final puzzle)
Impostor Syndrome
Captain Verdeterre’s Plunder
The House at the End of Rosewood Street
Emily Short's Interactive Storytelling 
The “author’s notes” for Impostor Syndrome are also available: http://www.deirdrakiai.com/2013/11/16/impostor-syndrome-now-in-the-form-of-a-videogame/
Ah yes — as I in fact knew, but missed when I came back to do the roundup. Thanks for reminding me. I’ve added it to the list.
Now there are also design notes for Captain Verdeterre’s Plunder: http://www.rcveeder.net/blog/2013/11/25/thoughts-and-high-scores-on-captain-verdeterres-plunder/
Cool! Thanks for the pointer. I’ve added to the main post.
Hello,
On this page are the author’s notes for The House at the End of Rosewood Street:
http://incobalt.wordpress.com/writings/postmortem-rosewood/postmoretem-rosewood-text/
.
That’s probably the best page for a postmortem on Rosewood right now, though it’s based on an earlier, unreleased version of the game. The general design principles are the same; I just don’t get into the IF Comp experience or anything like that. Thanks for commenting on behalf of my game!