By the way, the reason for such restrictions on video length is likely due to a European tax on video cameras. Under European law, a video camera is defined as a camera which can shoot more than 30 or more minutes of video, so you'll see a lot of cameras put a cap at 20:00 or 29:59 to avoid the tax.
#5. "RE: 3200 for video" In response to Reply # 3 Sun 24-Feb-13 12:59 PM by mareng
Thatcham. GB, GB
I have done a couple of short videos on my D3100. The first was some ladies Line Dancing at which I stood by a speaker so the music was very clear. I shot the video in short lengths of a few minutes each, then stitched them together with a bit of editing using the Nikon supplied Quicktime and the NX2 editing software. The video was shot in Landscape. I then converted with Convertelite (free software) to a .wmv file such that I could insert it in Microsoft Movie Maker so anybody could see it. This allowed me to add Titles and Credits. Another time I took some video clips of a Beefeater (guard from the Tower of London) giving a talk ( I was sat on the front row to pick up his voice clearly, though he didn't need a microphone being an ex RSM). As I didn't have a wide angle lens only the kit lens I had to shoot in Portrait. Now video doesn't change orientation unlike a still. I eventually found some free software that allowed me to rotate the video without any effect on the person. This was Videosoft. As long as you change the orientation before converting to .wmv then you are ok. If you convert then turn your person comes out rotund. You can then add to MS Movie Maker and add stills, credits, effects and transitions or another video. During the publishing stage at the end you can compress the file for emailing but then you loose sharpness. With video and music you can be up to 1Mb/second so a large file.