Elgg won't ship with any features. Why not? Elgg 1.0 won't ship with any end-user features; think of it as a social application engine that can power all kinds of different sites and applications.
Who are "we" to tell you what features you need? The original Elgg codebase came with profiles, a blog, a file repository, communities and an RSS aggregator. The classic Elgg will still be supported.
That's good -serving two audiences (shell for programmers; classic for out of the box non-programmers) and ultimately allowing free form development.
I think Elgg has a lot of potential - I have a number of Elgg sites running now - from a community of practice to research spaces to course and program delivery spaces. It is a many splendoured thing, with multiple applications and a capacity to evolve as your "users" evolve from students to researchers to professionals.