I have to respectfully disagree that your use of the music in your video falls under the fair use laws. Those laws are very specific about what is considered fair use and I don’t believe your use of music falls under that protection.
See the following link: http://fairuse.stanford.edu/overview/fair-use/what-is-fair-use/
I have discussed this issue with several attorneys and also numerous licensing companies. The big issue is that even though a wedding video may be a private video of a private event, the fact is the videographer is paid to produce a creative production based on the event. The inclusion of music, especially if it is edited into the soundtrack after the event, is done specifically to enhance the final product (make it more artistic, set a mood, create emotion etc. etc.) in a way that would make the finished product much better. Lets face it, a wedding video with no music, frankly SUCKS!
In doing that, you are basically saying that the artist who’s music you used contributed creative content to the finished product for which you were paid. In this instance, technically you owe the artist money for using his or her creative work. If you do this without the artists permission, or paying the artist, you are violating the copyright. This is why copyright laws exist. The artist owns the contact and has every right to dictate how it is used, especially in commercial terms.
When a bride or groom buys a CD or an iTunes download, the license they get for it does not allow them to include that music in a video production, no matter how private it is. The license allows them to listen to the music and enjoy it. Editing it into a production that they pay you for constitutes commercial use, which is illegal.