Many people have asked why Canon DSLRs such as the Canon 5D/550D/7D are limited to only shooting up to 29 minutes of video (HD video is limited to approx 12 minutes or 4Gb)
I understand that this is due to the tax & duty rules within Europe. If a device can shoot more than 29 minutes of video then it is classed as a video recorder and attracts an additional rate of duty. Still camera are not subject to this duty so we are able to buy the DSLR camera that shoots video at a cheaper price due to this limitation.