DVDs are great distribution media. They hold around 5GB of material, which is pretty good for most content, even compressed video. When I finish a video I might upload a lousy-resolution version to the web, but I'll probably burn a DVD or two for friends or family.
But know this about recordable DVD:
1) Video DVD's compress video using the MPEG-2 method, which throws out image data in order to make the files small. It is okay for a viewing copy of your videos, but since it's much less resolution than the video you shot, you probably don't want to store raw material this way. As a rule of thumb, you want to store/archive your videos in the highest, most unprocessed format you can. This means full resolution, uncompressed, unprocessed. DVDs are not this.
2) If you use the DVD simply as a data storage device, think of it as a CD that holds 5GB of data -- this represents about 25 minutes of Standard Definition video uncompressed DV, or 35 minutes of HD video, compressed to ACHD format. Like I said, this is good for finished cuts, but it isn't even a single tape's worth of raw video. If you have a lot of tapes, this isn't great.
3) Video DVDs must be prepared out of real-time, so getting the video into your computer then onto the DVD is a bit of a process and takes a little time.
4) Perhaps the most important drawback: Recordable DVDs have a relatively unstable recording substrate-- a layer on the disk that has a colored dye that works with the laser. These dyes fade over time, and consequently discs can become unreadable as the disc ages, usually far more quickly than either hard disks or MiniDV tapes lose reliability. Since DVDs have a shorter lifespan, they aren't ideal archive formats.
Put all these together, and I'd say that for everyone but the most casual hobbiest, skip recordable DVDs for long-term storage of your video.