It's hilarious: there are 4 different businesses in the same street I work on that all have Tundras as their company vehicle (2 catering bakeries, a rug store, and a sports memorabilia store) and they all have busted taillight lenses. The first time I saw how far our the side those lenses stuck out, my very first thought was "Wow...those are going to get busted right away...
As far as the tailgate things go, I've never once had to remove the tailgate because I was putting something heavy in the truck. Heck, I've put wheel ramps right on the tailgate in a 1988 Ford F-150, and driven 4-wheelers and snowmobiles right up it into the box. No problems at all.
There was already another thread on this truck in which someone posted video's of various trucks going over a very bumpy dirt road...the shaking the Tundra did was hilarious.
edit: I just remembered a time with the F-150 where I saw 4 people standing on the open tailgate, jumping up and down in unison, trying to see if they could get the front wheels of the truck to move. Of course, they were all idiots who all thought they were brilliant...however, my point stands...probably 6-700lbs bouncing on the tailgate, and it closed fine.