Nice list, shilsen. I'll point out that several of these spells are fantastic. Glitterdust lets you blind several opponents at once, which is almost better than fireballing them -- a fireball doesn't take them out of the fight as surely as blinding them does. And web is wonderful for dividing and conquering, especially if you've cast Freedom of Movement on the party tank (who can then charge through the webs with impunity, fighting monsters one-on-one).
Grease? Tons of fun. Cast it on the cleric's holy symbol, the archer's bow, the wizard's favorite wand. Or cast it on the ground in front of you, and point and laugh as the bad guys tumble at your feet.
And Plane Shift is great. Undead creatures can always get an insta-tan on the positive material plane, and just about any bad guy can benefit from the plane of fire. Sure, you won't get their loot, and if they survive you've made yourself a real enemy; but when it works, oh, the satisfaction.
Ironically, druids, who receive the most benefit from augment summoning, receive very little benefit from SF: conjuration. As near as I can tell, the only spells they have that benefit from this feat are as follows:
-The various cure spells, when cast on undead. Not a tactic often used in my experience -- druids get the spells later than clerics and can't spontaneously cast them, and often rely on wands for their healing; wands are unaffected by the feat.
-Neutralize poison and delay poison when cast on a poison-using creature. Never seen it in play, but it'd be cool in a very specialized setting.
-Wall of stone when used to trap a victim. Again, never seen it in play, but it could be nice -- although for the cost, there are much better ways of trapping people (wall of thorns, for example)
-Fire Seeds and Storm of Vengeance, for the less-important effects of each spell.
-Word of Recall, when used to recall an item in someone else's possession. Not that common an occurrence

.
Any I missed? Druids have plenty of conjuration magic, but few of their conjuration spells have saves; if they take this feat, it's almost exclusively for the huge benefits they reap from augment summoning.
Daniel