Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
Intel made a couple of points that cleared up a lot, starting off with the fact that TRIM is indeed alive and well in Linux, and it comes down to having the right software installed to take advantage of it. I was pointed to a PDF that explains how the command can be executed (section 126.96.36.199), and that's all that's needed for a software engineer to implement the feature, whether it be someone in charge of a distro, a piece of software, or a file system.
I was also told that it wasn't only ext4 that currently supported TRIM, but Btrfs, GFS2 and XFS do as well, with more to be added later if the file system developers decide to add it (hopefully, they will). Past the file system, there are two things that need to be in place for TRIM to work: a TRIM-aware Linux kernel or an application capable of passing the command (like hdparm) and of course, also an SSD that supports it.
Intel also stated that it's been working with Red Hat and upstream Linux developers to provide guidance on supporting the feature in their (and other) operating systems for its particular SSD. TRIM in general isn't SSD-specific, however, so if the support is there, then any distro to natively support it should do so with any TRIM-capable drive. Sadly, Intel couldn't state when the fruits of this guidance would be seen, but I'm hoping it won't be too long before something pops up.