DV.com has released a column explaining the ins-and-outs of editing HDV material. While the article speaks about the post-production process with a PC slant, the article effectively explains the process and differences of editing HDV and DV. From the article:

In the last episode of Technical Difficulties, we looked at editing long-GOP MPEG-2: video compressed not one frame at a time, but in groups of pictures. Long-GOP compression requires an NLE to fetch and decode multiple frames to display or edit only one-a considerable complication.

[...]

HDV is a specification for recording 16:9 HDTV on DV cassettes. The formatis main specifications call for both 720p and 1080i recording, with a 4:2:0 sampling structure: Chroma has half the resolution horizontally and vertically as luma does, just as it does in DVD, digital television transmission, and 625/50 DV and DVCAM. Long-GOP MPEG-2 is used to squash HD down to a bitrate suitable for DV tape recording.

[...]

With FireWire transfer and HDV-native editing, your workflow is almost identical to working with DV over FireWire. The data rate is low enough to make capture on single disks, including laptop drives, feasible. Plug in the camera, capture material from it, edit, and print back to tape (to HDV or to D-VHS). With most NLEs, the material is decompressed once (actually, each time a frame is displayed or processed) and recompressed once (after all of the effects on the timeline have been applied), so your finished program is only one generation removed from the camera original.

You can read the full article at the DV.com Web site.