As of Version 6.0, LightSources has been superseded by settings for Lighting.
Since Version 3.0 (released in 1996), LinkOpen has been superseded by LinkCreate, LinkConnect, and LinkLaunch.
Literal
(Obsolete Mathematica Symbol) Since Version 3.0 (released in 1996), Literal has been superseded by HoldPattern.
As of Version 6.0, LongestMatch has been superseded by the pattern object Longest.
Since Version 5.0 (released in 2003), LUBackSubstitution has been superseded by LinearSolveFunction.
As of Version 6.0, MeshRange has been superseded by DataRange.
As of Version 6.0, NotebookCreate has been superseded by CreateDocument, CreatePalette, and related functions.
As of Version 6.0, OpenTemporary has been superseded by functionality in OpenWrite.
Since Version 2.0 (released in 1991), Plot3Matrix has been superseded by ViewCenter and ViewVertical.
As of Version 6.0, PlotDivision has been superseded by MaxRecursion.