[Note added, December 6, 2012 -- I spoke with the Parks Department on November 1st and they said that the construction date has now been pushed back to Spring 2013. For what it is worth, the Parks Department doesn't have much control over what KDOT is doing... If the winter is nice they might wrap it up earlier.]
The projected completion date for the construction on the Indian Creek Trail closure at Switzer has been pushed back to some time in November.
The closure on the Tomahawk Creek Trail around the North Pond is completely blocked off from just north of College Boulevard (111th) south to the park around 114th. Personally, I'm just riding Mission Road/Tomahawk Creek Parkway between Lee Boulevard and the park.
They're pretty serious about keeping you off this path, and for good reason ... the recent storms have eroded the bank of the creek to within less than a foot of the path in some places.
I've never seen a No Trespassing sign for a trail closure before.
[Updated 7/17/2012 to say the Leawood Parks and Recreation website posted a message saying "The Tomahawk Creek Parkway Trail closure (south of College Boulevard and north of 117th street at the north lake) has been extended to August 1st."]