gdm-early login v/s readahead

[Clunixchit]

Since I installed FC5T2 (never regret it), I saw a lot of modifications. Hence I have got lots of questions :)

has gdm-early login been replaced by readahead?
or can enable both on FC5T2?

What is the difference between readahead and readahead_early?

[BoyWonder410]

i know this is an old thread, but, i'd like to resurrect it. what are the answers to these questions?