Northwestern (ranked No. 12 and 14 in the two major national polls) hosts Michigan (a consensus No. 8) in Saturday and Sunday afternoon games, as part of the Big 10's opening weekend. ESPN.com's Graham Hays has a column on the Northwestern program, heading into the Michigan series. You can also click for the Michigan and Northwestern preview pages for this weekend.
Though it would be fair to refer to Northwestern and Michigan as the Big 10's premier programs in recent years, Ohio State has created some buzz in the college softball community with a 20-3 record and national rankings of No. 14 and 17 in the major polls. On top of that, the Buckeyes will host Michigan State this weekend in the inaugural games of OSU's newly refurbished softball field.
In the SEC, No. 1 Florida hosts No. 6 Tennessee in a three-game series (doubleheader Saturday, single game Sunday). These national rankings are consistent across the two polls. Previews from Florida and Tennesee are available.