Live.com can hardly get any traffic and their search works. I had high hopes for Cuil but gave up when it became clear that their search results were simply bad or missing. They should have held a closed beta for 6 months.
http://www.alexa.com/site/ds/top_sites?ts_mode=lang&lang... has them at #4 (which seems unbelievable but definitely past the bar of very high traffic sites)
On Wikipedia there are listed more than 50 subsites:
http://en.wikipedia.org/wiki/Windows_Live
With many of these being used directly from Microsoft desktop software, it wouldn't be so unbelievable for Live.com to be #4.