Modifications:
1 extra Field
1 Template modification
Add New Field:
Go to AdminCP -> User Profile Fields -> Add New User Profile Field
Profile Field Type: Single-Line Text Box
Title: Xbox GamerTag
Description: Please enter your GamerTag here.
Field Required: You can select here if you wish to have GamerTags required upon registration or not.
Click Save.
Note the field ID, which you will need in the template code.
Template Modification:
Go to AdminCP -> Styles & Templates -> Style Manager
Select the Style you wish to edit. In the dropdown menu select Edit Templates
Find Postbit Templates - edit either postbit or postbit_legacy
Find:
PHP:
<div>$post[icqicon] $post[aimicon] $post[msnicon] $post[yahooicon]
Add this below:
PHP:
<!-- / Xbox Card Hack -->
<if condition="$post['field_XX']">
<iframe src="http://gamercard.xbox.com/$post[field_XX].card" scrolling="no" frameBorder="0" height="140" width="204"></iframe>
</if>
<!-- / End Xbox Card Hack -->
When you create the new field make a note of the field ID you will need to substitute the _XX with the GamerTag field ID number.
Nearly finished... Now just Edit your Profile and enter your GamerTag