Here's the official word from Apple - full review of Logic 9 coming soon.
"The new Amp Designer and Pedalboard plug-ins give guitar players incredible new recording and sound design capabilities. Amp Designer recreates 25 legendary vintage and modern amp heads in beautiful detail with matching controls and 25 paired speaker cabinets that emulate the sound and feel of a guitar running through a real tube amplifier. Guitar players can create their own custom rig by mixing and matching amps, cabinets, reverbs and EQs, and can choose from three different microphone types that can be positioned in 3D space to capture the ideal guitar tone. Pedalboard adds an assortment of 30 guitar stompbox pedals that can be arranged in any order to produce a wide variety of lush, creative effects including overdrive, distortion, fuzz, delay, chorus, flange, phaser, tremolo, treble boost, wah and more."
"Flex Time is a new collection of tools that allow musicians to quickly manipulate the timing and tempo of recorded audio, including vocals and instruments, to create tighter performances. Using the Flex Tool, individual beats in a waveform can be moved effortlessly with a mouse click, without the need for tedious slicing and editing. Audio Quantize can instantly fix or adjust the timing of an entire performance by aligning notes and beats to a musical grid with a single menu selection. Varispeed provides the ability to slow down and then speed up an entire multi-track production to help record challenging parts. Flex Time also enables recorded tracks to be moved between different Logic projects and matched together, even if they were performed at different tempos. All Flex Time edits are performed non destructively and in real time, even when using the highest quality settings."