[RythmnSylver]

Improved Ability
[spoiler]Cost: .5 per level (Combat skills), .25 per level (Physical, Social,
Technical skills)
This power gives you additional dice for use with a specific
Active skill. Dice purchased for the Active skill carry
over equally to any specializations of the skill you know. You
cannot have more additional dice than your base skill rating.
Improved Ability does not actually improve a skill’s rating,
it only provides additional dice for tests involving the skill.
Improved Ability must be purchased for a specific skill, not
a skill group.
This power costs .5 per level for all Combat skills and only
.25 per level for Physical, Social, and Technical skills.[/spoiler]

Is it just me or does the RAW of this power mean, with a specialization, you get a additional 2 die then someone with out this power and the same specialization??? Or am I just seeing things??

[JustADude]

Okay, I don't know which book you got that from, but the current SR4A wording is as follows:

[spoiler]Improved Ability
Cost: .5 per level (Combat skills), .25 per level (Physical, Social, Technical, and Vehicle skills)
This power increases the rating of a specific Active skill by 1 per level. A skill’s maximum modified rating equals its base rating x 1.5.
Improved ability must be purchased for a specific skill, not a skill group.[/spoiler]

[Dr. Meatgrinder]

Looks like the version you're citing acts as a dice pool modifier.  The emphasized text just means that the modifier the power gives is not limited by whether or not you're using a specialization (and stacks with the specialization modifier).

In SR4A, the power augments the rating instead of acting as a DP modifier.  But you're more limited in how many levels of the power you can take in SR4A, since you're limited to 1.5 x unaugmented rating (so you'll never benefit from more than 3 levels in a given skill, since max unaugmented rating is 6, or 7 with Aptitude), whereas the version you're citing could be taken up to (skill rating) times.