Usplash which was used in Ubuntu 9.04 was replaced by Xsplash in Ubuntu 9.10 to provide a faster boot. Now, the Ubuntu team is replacing Xsplash with Plymouth.
Plymouth is already in use Fedora. The reason for switching to plymouth is because xsplash was not able to provide a flicker free experience as expected.
The use of plymouth means that Kernal Mode Setting (KMS) comes into the question. Karmic was released with KMS driver only for intel hardware. However as Fedora 12 has support for both NVIDIA and ATI hardwares, it is expected that the same will be available in time for Lucid. Here is a guide to setting up Plymouth on Fedora in case you face any problems.
For hardware not supporting KMS, it is expected that it will fall back to a "reduced look and feel", which provides a similar experience to uspalsh.