Fun, good movie in the format of a 1970s disaster film epic, with aliens as the disaster, tearing down differences and uniting everyone. It's a rather positive message of "We can get along." and that things will work out, compared to today's
blockbusters.
Recently, the web movie critic MovieBob did a video on it via his series, "Really That Good", which argues why, in his opinion, it's a great film, and I agree with a lot of it. Here's a link:
Really that good
Does the film seem dated? A bit, but in a good way, in which people could be happy and smile in films, not have blatant 9/11 themes, US military worship that is overblown, women being nothing but sex symbols, or racist caricatures. Is the killing them through a computer virus silly? Absolutely, but it is a reference to War of the Worlds.
If you ever get the chance, try and watch the special edition, it includes a few more plotlines, fleshes out the characters even more, and makes everything more rounded out.
Overall, the film is a fun ride, worth a watch.