Steam ID requirements:

[Kc]

For showing the Steam GamerCard, users must do the following:
Login to steamcommunity.com (http://steamcommunity.com/) -> Edit my Profile -> Copy the text from the "Custom URL" box into the Steam ID field.

If you don't do this, your profile link will not work.

THEN. Copy the URl and go to:
http://steamidfinder.com/

And you will get your real Steam ID. Paste that into your profile, and you're all set.

A lot of steps, but it works and you only have to do it once.

[DannyBox]

What is the point of having Games IDs? Kc

[Kc]

This is if someone wants to put a link to their profile in their postbit. See the xbox thing under my name? That links to my profile. A lot of people here play games with each other.