We killed Razor Monday night on 10 man. She's tricky, but if you stand around long enough, you'll find people to tell you she's easy and 'ur just bad' I hate those people.
We had 2 tanks, both prot warriors that jumped on mole machines as soon as they surfaced and immediately when mobs came out, we TC'd and SW'd to lock them down. We had our rogue beating the hell out of watchers and they melted. Guardians got eaten up by AoE. If a Sentinal pops up, the other tank peels any other mobs off that tank one by one and we range him down.
We set up on the far side of the area and split the tanks apart with everyone else in between. It was simply a matter of efficiently DPSing the adds and staying out of the fire. When the harpoons were ready, we sent a ret pally over to shoot em and finished off any watchers still up. Tanks drug the remaining guardians over to beat on Razor and they generally died to incidental damage like rogue's blade flurry and shockwave, chain lightning from the shaman, consecrate from the pally, etc.
It wasn't too bad handling all the adds with just two tanks but alot depends on the frequency of Sentinal spawns. They suck and it seems entirely random.
For us, this was hard but my 10 man raid is pretty casual and we expect to be on a longer learning curve.
your hat may be nice, but I have the little white tank top that says Legendary right across my boobs. I win. (or more correctly, H wins)