It seems that many raid leaders eschew one-on-one contact, preferring to post information and requirements on forums. The idea, then, is that no one is getting singled out. No one is being "picked on." That makes a lot of sense; you never want to give a raid member the idea that he's being singled out unfairly. But when you're in the situation that the raid isn't going so well, you need to get the raid going more than you need to avoid that issue.
Go ahead and poll each member of the raid, and ask them how they feel about things. Do the raid times work out? Do they still love the game, or has Cataclysm given them some angst with their class? What can the raid members do to help them get ready? After all, the problem could simply be bad luck with heroics.
This kind of individual attention is what's needed to make sure folks feel involved and valued; often, that feeling is all it will take to get folks back in gear.
If you're having trouble filling your raid, it might be time to doublecheck your raid times. After all, the last time we raided heavily was a year to two ago. In that time, people have moved and jobs have changed. Schedules have altered. Heck, for that matter, entire babies have been born.
You can't assume that the schedules that worked in Wrath of the Lich King will work equally well for Cataclysm. If you're having trouble getting the raid group filled, that might be one of the best places to start.
I'm not speaking for anyone else here, but I've played my paladin since way back when we kicked open the doors to Cataclysm. It's mostly the giant pixelated hamster wheel known as achievements that keeps me on him; except for losing all of those cheesements, I'd be a double-furry worgen druid already. I doubt I'm the only one.
The nice thing about Cataclysm is that it's a great time to try new things. Let people switch up their roles and swap places around. Especially if raid members are curious about playing one of the new races, a little bit of change might be just what you need.
Conventional wisdom has it that sharks need to keep moving to stay alive. Raids are a little like that. If you start canceling raids or stop trying to move forward, doubt and apathy will set into the raid members. People will question the viability of the raid, and that doubt can grow into a raid-killer.
This is all no good at all. Even if you don't have enough people for a 10-man raid, throw together a heroic and go do that. Check on Tol Barad. Perhaps even explore PvP. The idea is that you have 10 people who want to hang out together and do content; you should try and get them in to see some content.
Of course, some moderation is called for here. If you find yourself making alternate plans every raid night, you need to get yourself overhauled ASAP. In general, you have one week's worth of alternate plans when you can't fill raids before people start looking elsewhere to go raid.
Ready Check shares all the strategies and inside information you need to take your raiding to the next level. Be sure to look up our strategy guides to Cataclysm's 5-man instances, and for more healer-centric advice, visit Raid Rx.