Ferret said:
How does the wheel work? What way does FR do it now.
The Great Wheel is the standard D&D cosmology: From the Material plane branches the Ethereal plane and the Astral plane. The Ethereal plane is mainly useful for going ethereal[1], but through the Astral plane, you can reach the Inner and Outer planes. The Inner planes are the elemental planes and the energy planes (positive/negative), plus various combinations of these (para-elements between the elements, and quasi-elements where elements meet energy), and the Outer planes are alignment-based. The Outer Planes are arranged in a big circle with the Outlands/Concordant Opposition as a "hub", and this circle is the reason it's called the Great Wheel. There are 17 outer planes, one for each of the nine alignments and eight planes for the border sections between the alignments other than True Neutral (e.g. Mount Celestia is Lawful Good, Bytopia is Lawful/Neutral Good, Elysium is Neutral Good, Beastlands is Neutral/Chaotic Good, Arborea is Chaotic Good, and so on).
The default FR cosmology does away with this, and just has various outer planes that don't have any particular connection to alignments or one another. That is, instead of Lolth living in the Abyss in a realm called The Demonweb Pits, she now lives in a plane called the Demonweb Pits.
There are some rather strong reasons for not using the Great Wheel cosmology for many worlds. For example, the alignment-based structure means that there will be dissonance when applying it to real-world pantheons: Tyr is Lawful Good, so he should be on Mount Celestia. However, the other Norse gods live in Ysgard and according to mythology, so should Tyr. The problem with doing that for Forgotten Realms is that FR has been using the old cosmology since 1987, and now for some odd reason it doesn't anymore.
[1]This is a change from 2e, where the Inner planes were accessible through the Ethereal plane, not the Astral plane.