OK. So I was messing around on chardev.org trying to figure out what gear selection I can easily get my hands on. Things to note:
1. I haven't played in a few months so my gear and what not is outdated. I intend on playing soon (school currently). I do know that when I get back I can get into a guild that is through SSC/TK and working on the start of T6 content.
2.The spec on the CharDev is funny, I know, but it allows for me to be of a bit more use DevSpamming when I'm not needed to tank and can simply DPS. I've tried it on my character a while before and it works surprisingly well.
3. I do know that the rings have the +4 stats on then when I'm not an enchanter. I plan on leveling that up instead of mining.
So the question. With the gear I have selected on Chardev.org, would I be able to tank T6 content effectively? I do know what I'm doing as a tank and have been tanking since I've hit level caps (60 and 70).
Any input on spec, gear or anything of the nature would be awesome.
I think that would be sufficient for early BT/Hyjal. I would encourage you to change some of the gems around. There are several places (chest, weapon, shield, ranged, waist) where you could follow the socket bonus and pick up 4 def/4 dodge at the sacrifice of only 3 stam by using 4 def/6 stam or 4 dodge/6 stam gems.
I would also encourage you to look into your spec a little more. I think that not having focused rage is a big mistake.
Overall, it looks like you should be fine. Good luck.