I've got 2 installs, only one with this bug.
1) Nvidia 8600GT graphics card on HP Elite 8200. No issues with Plymouth.
2) Intel GM965 Integrated Graphics on HP 6720s Laptop - Text is shown on bootup instead of Plymouth.
Linking this to Bug #1171195 which is the same, it seems that the problem is with Intel Graphics.
I've got 2 installs, only one with this bug.
1) Nvidia 8600GT graphics card on HP Elite 8200. No issues with Plymouth.
2) Intel GM965 Integrated Graphics on HP 6720s Laptop - Text is shown on bootup instead of Plymouth.
Linking this to Bug #1171195 which is the same, it seems that the problem is with Intel Graphics.