They're both still in somewhat early shape, but their inclusion in the last Karmic Koala alpha before beta indicates they're here to stay. The new xplash bootup will transition directly from a BIOS boot-up screen—and a newer GRUB chooser, if it's a dual-boot setup—to a graphical loader with a progress indicator, and then straight to the desktop if the user doesn't select a username chooser or password protection. Check out a (suspiciously slow-moving) video capture below:
As for the Software Store, it's present in Alpha 6, embedded in the System menu. It has a spare, unfinished look at the moment, but it also seems dead set on making software installation simple, which is a promising direction.
You can check out more screenshots and details of the latest Ubuntu 9.10 alpha release at Softpedia. While we're peeking at the next release of Ubuntu, check out a few of the community-developed themes that could make their way into the default offerings for Ubuntu 9.10.
Ubuntu 9.10 Alpha 6 Has Ubuntu Software Store [Softpedia]