Set the process property of the column you want to format, like this:
colModel: [
{display: "ID", name: "id", width: 40, sortable: true, align: "center", process: procMe},
{display: "Title", name: "title", width: 180, sortable: true, align: "left"}
],
notice the process: procMe on the first col, and then:
function procMe(celDiv,id) {
$(celDiv).html("Some formated text/icons/pics or whatever here");
};
I don't have a way to try it right now but i think it should work, sorry if there are any mistakes i just wrote it from memory and i might have forgotten something.
Hope it helps...