Well, my company has had a small fleet of Libertys since they were introduced, and I can tell you that most of them do the same thing. They don't "bang" into gear when driving normally, but will do so under certain circumstances. Honestly, these trannys aren't that sophisticated, and it doesn't really seem to hurt them. It seems to be more of a lack of refinement. That said, we have had a few trannys die on us, but we use the Libs off-road quite a bit. They lead hard lives.
If yours does this on every shift or downshift, something may be wrong. One other thing to check would be your shift linkage. It may be misaligned, and may be causing the bang into neutral.