Comparisons of Wheel of Time with Lord of the Rings,
which came up as the series was gradually published,
focus on two points:
the length and complexity of the world-building and story development,
and
the apocalyptic darkness-versus-light scenario.

More recently, the comparisons have let go of Tolkien
and have been oriented around
Robert Jordan compared to George R R Martin.
Special effects, as Iains points out,
as well as a cast of multitudes
with many rivalries and conflicts,
and wildly contrasting climates and cultures.