I use accuweather. I like it the best. Also have the weather channel, but don't like it quite as much. If you want BEWeather, it is free from RIM right now in Appworld for BB 7 devices, the Torch 9810 included.
BerryWeather (BeWeather) is one of the $77 in free apps that RIM is giving away to people who purchase an OS7 device. You get the full version, no limitations, which is much better than the original free version.