I'll only admit to about 10 - 15 hours (including reading other blogs).... it does depend on the week, and whether I've got a "real" work project! Don't want to look like I neglect the kiddos too much, don't ya know...
I should start tracking how much time I spend actually blogging. But to venture a guess, probably 10 to 15 hours a week right now. I plan on upping that though now because my hours just got cut at my part time job, so I am looking for more blogging opps! I love to write!!!
When I just had LuluMom, http://lulu-momblog.blogspot.com/
about 3 hours a week, including research, etc.
Now that I consult for MadCap, http://blog.madcaplogic.com/
add about 10 to that. Again, timely posts, well researched, and all.
But, did I say how much I love it!