I, for one, find it refreshing that SWTOR has most pulls be multiple target pulls. Solo-levelling feels much more epic when you waste ahandful of MOBs rather than one at a time. I think this model continues in flashpoints.
Honestly, if a DPS pulls a strong, or even an elite, in a flashpoint, I think they are able to handle it. I like it, and I think it adds to the epic feel of the fight. As a tank I don't want to simply be the guy mobs wail on.
As tanks we need to mark targets (I suggest another thread to discuss the marks and what they mean: CC, Focus Fire, etc. hopefully to be stickied). I mark the BBEG with a shield. Thats my primary target, whom I am going to focus on make sure it sticks to me. I use Bullseye for focus fire. I want dps on bullseye. I will typically force leap to shield, smash, then switch to bullseye to build more threat, using taunt on shield if needed.
3rd and 4th target (lightning, lightsaber, etc) are cc targets if you want to cc. Pick the ones outside your smash radius. If you want to forgo cc, fine, just let DPS know if they pull targets 3 or 4 before bullseye is dead, they are on their own.
As for healers, they get a lot of threat from healing a) Tanks who don't mitigate and b) Dps who act like tanks. There is a heal build (I forget which) that does a lot of overhealing that generates threat, so healers, watch the overheals until they fix it (if they fix it).
Other tank builds do hold threat very well. But, they also make healers work harder since they do not have all the mitigation tools Juggernauts have.
For the WoW fans, Juggs are like Warriors. In these early levels we need a lil more time to build rage so we can bring all the threat into play. But a well-played/geared/specced warrior is an awesome tank, and I feel (fear?) Juggs will be the same way.
Simplest solution is to ask a group to count to three before dps/healing on boss fights.