I've had an on going seatbelt warning light issue, it stays on when the drivers belt is buckled, and well only shut off when both sides are buckled.
I replaced the drivers side buckle, no difference.

Any suggestions on what to check next?

The fact that the light goes out when you buckle the passenger side belt means the problem isn't in the belt or buckles. Your OCS system (which "weighs" the passenger to determine whether it's none/baby/juvenile/adult) thinks there's someone sitting in the passenger seat. If you don't find any problems with the wiring under the passenger seat, chances are the bladder which does the weighing is shot. That's bad news, because I'm pretty sure it means replacing the whole lower seat frame to the tune of about $3000.

I neglected to mention that I also replaced the passenger lower cushion that has all the sensors in it, is there another in the frame?
The car has been to the dealer for various issues, each time the light has been on, each time they claimed it was related to the problem, first it was front wheel bearings, second was for the brake booster, I was skeptical it was related and said so, they said I was wrong.
I was reading my owners manual and found that the seat belt system is warrantied for 10 years from the in service date, I've got a little more than a month to go.
I think I'll call corporate.

The OCS is only indirectly related to the belts, I don't think it will be covered. There's no calibration for the bladder systems like there is for the ones using load cells in the rails, so if you've already replaced the bladder and controller, I'd say you most likely have a wiring issue. Either loss of power to the OCS C/U or an open circuit between the C/U and the Bag Brain under the console. I'd remove the seat and have a very close look at the seat harness, and also strip the cover off the wire loop connecting the seat to the car and do a close inspection for fatigued or broken conductors.

Corporate confirmed the 10 year warranty, I'll give the dealer a call.
Are you a Tech?

Nissan/ASE master tech, yes. The dealership will need to run the specific OCS part number through WCS (Warranty Call Center) to see if the part is covered under the belt warranty. I wouldn't trust the Customer Care reps to know about that.

Thank you, I appreciate your expertise.
Do you agree that their relating the belt light to wheel bearings and brake booster was incorrect?

Yah, that seems far fetched. Vibration can only have a marginal effect on the OCS system, and it certainly can't cause a constant belt lamp.

The bearings were causing the ABS to trigger when coming to a stop.

An unrelated question, where the front bearings went at 80k miles, should I plan on replacing the rears soon?

Nissan wheel bearings are kind of a crapshoot, some fail prematurely like yours and others outlive the vehicle. I've always wondered if it's perhaps a "production lot" thing, because it does seem like they often fail an axle at a time instead of a bearing at a time. In light of that, I wouldn't plan. The rears might go forever. However, if they don't, it's probably safest to replace both if and when the first one fails.