Spell Compendium
I picked this up at Gencon Socal this weekend.
It's an incredibly useful book. As others have stated, having all the spells in one place is a big deal.
There are a lot of spells I've never seen before. Some change the game in significant ways.
For example, both the druid and the cleric now have a spell that lets you raise someone from the dead with no level loss if it's cast within a round of death (well, the druid one reincarnates).
There are a lot of new ray spells. Playing a ray specialist seems a lot more viable with this book.
Anyspell/Greater Anyspell are core now, presented as part of the Spell domain.
There are a lot of new ranger spells, including one that lets rangers shapechange into a wolf for 10 minutes/level as a 1st level spell.
Wizards get a spell, Ball Lightning, that really rocks. It's like Flaming Sphere, but it's 5th level, and instead of the sphere doing a fixed 2d6 fire damage, it does 1d6/caster level (max 15d6) electrical damage (reflex negates). Since it lasts 1rnd/level and can be directed as a move action, I see this becoming a staple spell for wizards and sorcerers.
There's a whole Bite of (Wererat , Wereboar, Wearbear, Weartiger) series of spells that druids and sorcerer/wizards get, which last 1round/level and provide significant stat bonuses, natural armor bonuses, the blindfight feat, and claw/bite attack routines. Bite of the Wearbear, for example, is a 6th level druid spell that gives +16 to STR, +2 to Dex, +8 to Con, and a +7 enhancement bonus to natural armor. A wildshaped druid who then casted this spell would be a terror indeed.
Wizards get a series of spells based on the Planar Ally series, but which summon dragons instead; they have an XP cost, and the dragon must be payed in gold, but it will then fight for the party. These spells seem very powerful.
Sorcerer/Wizards get Greater Enlarge Person (Enlarge Person, but 1hr/level) as a 5th level spell.
Clerics get Faith Healing (like cure light wounds, but always get an 8 on the die, can only target worshippers of same god) as a 1st level spell.
Sor/Wizards get Floating Disk, Greater -- like Tenser's floating disk, but you can sit on it and command it to carry you about. It's a 4th level spell -- 1hr/level duration. Very cool ;-).
Sor/Wizards get GemJump, a spell which lets you teleport back to a specially prepared Gem. Since you cast this spell once and it works until triggered, it means a Wizard who has prepared this can have the ability to teleport home without having to memorize a spell to do so.
-Ken