Skinny Ski is the go-to website for the cross-country skiers I know. It's got nearly real-time reports from actual skiers out on the trails.
In Duluth, you get really fresh reports on city trails, especially Piedmont, Hartley and Lester. Also the private trails at Snowflake get frequent reports.
Reporting is a little spottier up the North Shore. The folks at Sugarbush report frequently, as do their skiers. Pincushion ski trails are updated about twice a week. And the folks up the Gunflint Trail provide detailed reports at least weekly.
For the North Shore state parks, sometimes the best info comes from their weekly reports, filed by the park managers every Thursday.
The skiing is pretty good everywhere right now...get out and enjoy!