We're DVC members as of about a year ago, but we're likely to buy another timeshare (probably Hilton or Marriott) in a few years. Right now, we have one small child and we're hopefully soon to have another (we're waiting to adopt). DVC makes a huge amount of sense for us. We were going to WDW every year, sometimes twice a year, because we have always loved spending time together there as a family. I have always really enjoyed it, so I know we'll continue to want to visit even after the kid/s grow less interested.
We bought DVC first because we were consistently going to WDW, we always stayed at deluxe resorts, and we often went with additional family members and so needed two rooms or a large suite. We bought enough points to get a two bedroom for a week at just about any resort in at least one season. In practice, we think we'll generally go for 5 or 6 days in a two bedroom and do a second smaller trip for a few nights. (We had double points this first year, so we've taken extra trips.)
Once the kid/s get older, we plan to do a lot more diverse vacations again. (I'm afraid the vacations I most enjoy with young children are cruises and Disney. Long plane flights with toddlers fill me such dread that it doesn't make for a relaxing vacation.) We love Hawaii, and so we think we'll either buy an every other year timeshare there or get enough points to do every 3 years at the DVC they are building there. We're not going to make that call yet, as we don't know what we'll think of the DVC at Ko'Olina and we don't know how it will compare in price to the timeshares already there. We like the Hilton Hawaiian Village on Waikiki, and my DM just stayed at the Marriott Ko'Olina and liked it pretty well. We know we could be reasonably happy with either of those options, but we are also tempted by the fact that with the Hawaii DVC, we'd be able to very easily use the points at WDW if we didn't feel up to the long flight some year.
We've also thought about buying something just to use as a trader. I've spent time reading over on TUG, which I really do recommend if you're weighing your options. We're holding off on buying anything else until we feel like we understand the ins and outs of the particular system, and until we're ready to drag young children to more exotic destinations.
Hopefully, Dean will chime in soon. He's generally got great advice.