It may have the same look but there are small differences that you will notice. The same seed doesn't generate the exact same world. I ran into a similar issue on one of my worlds. I found a nice spot and started building but ran into a terrain feature that I couldn't modify enough (a river). So I deleted that world and used the seed to regenerate the same world thinking I would start building a couple tiles farther away. Things were not in the exact places that they were before. They had shifted by one or even 2 tiles and the height the tiles at was different by about 1 meter but it fluctuated. Some of the tiles were the same some were higher and some were lower. The nice large flat spot I had found wasn't as large or as flat as it was the first time around.