Welcome to Cruise Critic! If you'd like to participate on our forums by joining in the conversation, please Register Now! Be sure to visit our FAMOUS Roll Call forums, where you can meet other cruisers sailing with you and share a tour or shore excursion and SAVE MONEY!
The B008 is more compact and has a faster and nearly silent piezo-electric motor. Optical performance for both is similar with both dealing with the super-zoom compromises between convenience and image quality pretty well.
Here are links to full tests of both on SLRGear.com:
I had the older Tamron 18-270. I sold it and got the new one. The new one is smaller and lighter as mentioned. The old one had some auto focus issues particularly in low light. The new one is much better with the auto focus. It is a great all-in-one travel lens. As previously suggested, the all purpose lenses have limitations but this one works for me. My experience is I use the wide angle a lot and seldom shoot beyond 200mm. On a recent trip to Europe I also took a Nikon 50mm 1.4 and never used it. I took the Tokina 12-24mm and used it a few of times. I use a Nikon D300.