the most recent ratings on Rotten Tomatoes fansite says it's rotten, although about 50/50.
The NYTimes reporter liked it, but my favorite comment was that it was an Irwin Allen movie...actually, I liked Irwin Allens' movies, but didn't believe them.
Most of the "positive" reviews assume that the movie is aware of it's campiness.
It just occurred to me. The reviews that I have read have led me to one comparison. "Day After Tomorrow" has the same effect on audiences as "Springime for Hitler".