Might be wrong here but do the latest gen SSD's still need TRIM? Meanwhile idle time garbadge colection is so well optimized that for example anything based on a Sandforce controller seems to work perfect with OSX.
Absolutely need TRIM ? No. However, it is a "nice to have" when processing tons of I/O and don't have much idle time and a limited over provisioning budget. So mainstream need? no. Very high performance and usage yes.
TRIM is no where near the panacea that folks were trying to make it out to be 1-2 years ago. It also doesn't work if drive is behind a controller on a non SATA bus. (e.g, on USB 3.0 , RAID controller , Light peak , etc. ). Any vendor who is leveraging TRIM as their primary 'free list' expansion mechanism is severely misguided. Don't buy from them.
Need TRIM so that support wider variety of SSD drives? Apple doesn't really support them now. Not sure why they would be eager to even remotely encourage folks to stuff a wider variety of them into their boxes.
If Apple isn't going to roll out a significantly better file system then TRIM is something useful to incrementally add to the old one to make it have marginally more utility/value.