My son just loves Thomas & Friends. He collects the trains and has watched a number of the original series. This was our first foray into the newer Thomas adventures, and I thought it was well done and kept much of the original flavor and ideals.
Animation (versus the original's use of real-life models) has both pluses and minuses. On the plus is the allowance for greater flexibility in camera shots, more animation of the figures themselves and a wider allowance for possible story lines. On the negative, there will always be something magical about real-world objects when done as well as the original series was.
As for this particular outing, it involves a mysterious island, colorful new characters and adventure as always. The narration is well done, as are the character voices (one major difference with the originals, which are all voiced by the same narrator). The scariest moment being a near "deadly" plunge off the train tracks to the cliffs below.
Nothing too frightening, good values (usefulness, obedience, friendship, etc) and charming visuals should appeal to younger children. It's also nice to have storytelling without frenetic action... a good choice for parents.