I've run two conjurers lately, one with Abrupt Jaunt, and one with Enhanced Summoning and Rapid Summoning. Let me say this: if you can summon monsters as a standard action, you are doing VERY WELL. A straight-up malconvoker build is hugely powerful in this regard. There's a lot of paperwork (since you have to look up the Tiger, apply the Fiendish Template, then modify for Augment Summoning AND the malconvoker ability. It's hugely powerful, though, especially once you get fiendish legion (double the summons!)
My malconvoker, however, met an untimely death. He was invisible, and I thought protected from harm by some crocodiles, but in the end he was done in by a bunch of beads of force. The bad guys tossed beads at someone else, my guy just happened to be too close. A number of 5d6 - no save at all - splash damages will do people in eventually. The ironic thing is, since he was invisible, he was the only guy not actually encapsulated by the bead, meaning everybody else was eventually protected from all that splash damage by the sphere itself.
My abrupt jaunter (he's a beguiler/conjurer/ultimate magus) is nigh impossible to kill. Between improved initiative (I did the fighter-feat swap for scribe scroll) and nerveskitter (transferred to the beguiler list via the Ultimate Magus's ability), I always go first. Abrupt Jaunt makes him REALLY hard to hit more than one or two times per combat (have to center an AoE on him, usually), and there's always lots of interesting things to do with the ability. It's GREAT, but you can't be a monster-summoner type of conjurer with abrupt jaunt. On the down-side, this character does a lot less damage overall. He is still pretty effective, but the debuffing / battlefield controlling types of spells are starting to become harder and harder to pull off as challenge rating goes up. More and more bad guys have teleports, flight speed, freedom of movement, huge grapple scores, and excellent saving throws. I actually find myself doing more and more of the conjuration direct damage spells (blast of flame, Orb of Foo, etc).
All that said, I also STRONGLY suggest you look at the Summon Elemental reserve feat. It's astoundingly good. Learn the languages so you can talk to them, and they're super-handy. Get them to trigger the traps your rogue doesn't want to fiddle with, scout around and report back (earth glide is GREAT), or just spend a standard action to summon up a flanker for your rogue.