What? What gave you that impression? That's a really old version. Here's the last 3.3 Windows build:
http://bitbucket.org/tortoisehg/files/downloads/tortoisehg-3...
This was from the downloads page:
http://mercurial.selenic.com/downloads
Edit: Oh, crap, I completely misread that. You were talking about the git Windows version. Oh well. Mercurial Windows versions are staying quite up-to-date, thanks to the tireless work of Steve Borho.
https://bitbucket.org/edgimar/crecord/overview
If you want a "staging area" just use a temporary commit and keep ammending it with `hg crecord --amend`. There really is no difference between a commit and a staging area except the name. If you're afraid of pushing your WIP commit, use `hg crecord --secret` or `hg commit --secret` so that your commit will be in the secret phase and won't be pushed until you declare it draft with `hg phase --draft`.
I started using Mercurial because the basic interface and operations appeared more natural to me. Also, at least at the time, the Windows support was better in Mercurial.
After working with some repos using Git, I fell in love with the staging area, and the ability to selectively stage parts of files. I am sure Mercurial has something similar, but it was built into Git.
The only thing that bugs me is that the Windows port appears to be stuck at 1.9.5 (yes, I know it's open-source so I should go fix it instead of complaining).