AKV has a really neat "exotic" feel to it. You really feel transported to an African safari lodge.
I've stayed at OKW once, and it really is a beautiful resort. Here are some of the main differences you'll likely notice:
--OKW feels like a community, almost like a development where people might live. AKV Jambo House feels more like a resort. The villas at AKV open into interior hallways, and it feels more like a regular Disney resort than like a community. That being said, the resort-like feel can be a real plus. You've got easy access to great dining (Jiko and Boma are both wonderful), a short elevator ride down to the pool area, and plenty of activities for the kids to do indoors during one of those famous late summer Florida rain showers.
--Like the previous poster mentioned, OKW has a pastel, light and airy decoration scheme. AKV's is more dark tones. Neither is really better than the other, it's just personal preference. Just get in a safari mindset, and absorb all the cool details Disney built in--like Lion King tiles in the showers and Simba heads on the back of the dining chairs.
--Jambo House offers valet parking or self-parking. You won't be able to park as close to your unit as you can at OKW, but you can get luggage help or take advantage of the free valet service available to
DVC members.
You may also be pleasantly surprised by how enjoyable and relaxing it is to watch the animals on the savannahs. There are tons of public viewing areas scattered around the resort, so just go find a non-crowded one and sit back and enjoy.
Also, AKV has lots of great activities. When we were there last December they had cookie decorating for the kids, bead necklace making, medallion rubbing, and a craft to make Christmas ornaments out of ostrich egg pieces. They'll give you a list of what's available at check-in. They also have night vision goggles you can use to see the animals on the savannahs at night. I haven't tried that yet, but I've heard it's really quite neat to see.