Scent: Both the body butter and the lotion smell of vanilla and shea butter. The distinguishing factor is the narrower radius and shorter duration of the body butter's scent. Despite a stronger scent, Dove's lotion is nowhere near overwhelmingly sweet.
Texture: From its appearance in the container, I had expected the body butter to be fluffy and light. Totally contrary, the body butter scooped out like a paste, but does easily blend into the skin. Dove's lotion squeezed out of the bottle a lot lighter, and is similarly smooth and fast absorbent.
Hydration: The body butter is advertised for "Very Dry Skin" while the lotion is for all skin types. I found both equally moisturizing, but Dove's lotion leaves my skin much more silkier.
Price: The body butter is 200mL vs Dove's 250mL, but since the body butter is rather dense, it would probably last as long as Dove's lotion. I got the body butter for free at a L'Oreal event and bought the Dove's lotion on sale at 50% off. Regularly, the body butter retails for £13.00 vs. Dove's lotion for about £3.
Recommendation: Dove's lotion wins on price, texture and scent to be the better deal. I would continue to use the body butter for spot treatments, but Dove everywhere else. So if you already love Body Shop's Shea Body Butter, then Dove's Winter Care lotion would definitely step up as a bargain alternative.
Update (Jan 12, 2013): I used up the Dove Winter Care, after using it almost daily, minus the two week vacation I took over the holidays. The 250mL lasts about 5 weeks of use.
Update (May 30, 2013): Updated impressions for the Body Shop Shea Body Butter in my May Empties.