We went in Feb 2012 (2/11 - 2/17 to be exact) and it was pretty much heaven! The year we went it was before President's Day Weekend so crowds were very low and the last day we noticed the crowds started to pick up quite a bit.
The biggest pros are that prices are low and crowd levels are low (for early Feb like you're considering).
We thought the weather was very nice when we were there, since we were coming from snowy weather in WA State. Mornings were chilly enough to need a jacket/hoodie/sweater, but it warmed up to around 70 most days. We never got chilled in the evenings. One morning was downright COLD. Overall, we enjoyed the weather and we didn't have any rain the entire week.
All of the water rides were open when we were there, including Splash Mountain and Kali River Rapids. It definitely wasn't as fun riding them in the morning when it was still chilly out but we didn't want to skip them. I read somewhere that they lower the water level and turn off the spraying features during the colder months, so nothing really sprayed us...though you obviously still get wet.
One major con is that February is a month that certain rides are still down for refurbishment. I missed out on Big Thunder Mountain Railroad because it was being refurbed and I was pretty heartbroken since it's a pretty major ride. Also, one of the waterparks is closed (alternating each year)...not that you would necessarily want to have pool time with it being a little colder out. The resort pools were mostly empty which is a bonus I guess if you would still swim in 70 degree weather.
Most rides were close to walk-ons...never waited in line more than 20 minutes and only used a Fastpass (legacy) here and there. It might be more important now with the FP+ system in place now though. We didn't have any trouble changing around our ADRs the day of, though we weren't trying for any character meals or anything like that.
We loved February and I would go during that time again except I was always worried about our flights due to weather, and in fact the day we flew to WDW they had to de-ice airplanes. That kind of thing makes me nervous so we will be going in late October 2015 this time.

Funny how we are opposites!