Technically, any machine Apple makes is more than adequate for editing home movies (and authoring DVD's).
I use my 600MHz iMac (G3) for video editing all the time, with no complaints. The only problem I've been having lately is exporting some of the more crunchy codecs seems to take *forever*, but I have a feeling I might need a fresh install of OS X (going on 3 years and have never formatted the thing).
Good luck, and enjoy your new Mac, whichever that may be!