Only the launch team itself will get listed in the manuals and in-game, but former members will still get credited elsewhere
Regardless of how important (and lucrative) Warhammer Online has proven for Mythic, the developer got its share of flack when VP and GM Mark Jacobs admitted in August that his company will not be crediting former team members for their contributions to the game. Jacobs reasoned there would just be too many cooks in the kitchen to list given how long the game was in development, and this didn't sit well with too many ex-employees. In other words, only Mythic developers on board during time of the "final" game's launch will be listed in the official credits. In light of criticism over this decision, Mythic has now reached a more reasonable compromise for recognizing the efforts its former team members.
In the newest International Game Developers Association newsletter, Mythic pledges to maintain an online database of current and former team members who contributed to their projects, including their older online titles. This was actually suggested to Jacobs by Newsweek tech editor N'Gai Croal. However, Mythic notes only those present during the official launch of a game will be credited both in-game and in the instruction manuals. Jacobs will commit himself to the IGDA Credits Standard Committee in order to "offer guidance on the issues and challenges posed specifically by MMOs", at least in terms of credit policies. For now, IGDA chairperson Jen MacLean seems rather pleased with Mythic's solution.
While we're not talking about severance pay or money owed, being listed in the credits is nevertheless a fairly big deal as far as developers are concerned. The credits helps verify their contribution to both the project and the industry. Of course, they also help with their resumes!