There's a post over on the BioWare Social Network forum, which goes into detail about the Dragon Age 2 PC DRM. Of course, Steam DRM is going to be packed with the Steam versions. Other versions though will authenticate themselves "after a select period of days" (still not specified). Here's the full info:

Recently there has been some concern over the DRM (Digital Rights Management) included with Dragon Age 2. Hopefully this post will help clarify what the DRM is for all versions of Dragon Age 2.

Steam versions use Steam DRM, no other DRM is added.

Non-Steam versions (digital or retail disc) are as follows:
- No disc check, you do not need the disc in drive to play.
- No limit on the total number of PCs you can install and play the game on.
- There is a limit to the number of unique/different PCs that can start/play the game within a time window [5 PCs in 24hrs].
- Each install requires logging in to your EA account to verify game ownership and if you are a member of these forums, you have an EA account.
- You can play offline but the game will require a login check after a select period of days.

Release Control (does not use securom)

- It does not install anything to the PC
- Sole purpose is to check with a server to validate whether the game release date has passed or not. - It completely removes itself after the game release date has passed
- You will not be able to play until that date has passed
- Dates & times are set to the retail street date per country.

Hopefully this explains the DRM included in Dragon Age 2.