Like the last few Snow Leopard builds released unto the world, 10A411 is billed as an under-the-hood enhancement; basically it is. But there are few noticeable upgrades scattered around, if you look reaaaall close.
Macrumors forums users, the dev-build-having, detail-discerning lot that they are, found a modest bounty. Quicktime X, seen below, gets a slightly overhauled interface, while the new, blackened contextual dock menus feature a slightly different font (above). Helpfully for Spaces users, Dock Expose now displays windows from all workspaces. On top of that, there's a new Safari build, though nobody seems to be able to find any differences from the last.