I've been using this for a while. It's great for quick editing on the go.
What it doesn't have that would really make it useful is the ability to import custom graphics with alpha channels so you can make "lower third" bars. This would be useful if your editing something on the fly for an event or something and want to add their logo. If you could do that, then it would be a great program.
imovie for iPad can't do it either, so there must be a limitation.