Good. I did it. The latest version of SlickGrid seems to have changed in how the title attribute is set in the column headers. Previously, the column name attribute would be set as the header. Now we need to add a new parameter to the column definition - . I edited your fiddle with this and now the tooltips work fine. toolTip
http://jsfiddle.net/100thGear/6sGXx/
I changed the column definition as follows:
{ id: "long-val", name: "Really Really Really Long Title",
field: "longVal", sortable:true,
toolTip: "Really Really Really Long Title" }
Please note that you do not need slick.autotooltips.js for this work. This is just for data tooltips.
Let me know if this helps!