I'll start off by saying that I think Rowan Atkinson is a comic genius. Mr. Bean, Black Adder, and The Thin Blue Line are all classic British TV comedies. His store clerk in Love Actually is absolutely the best scene in a great movie. That being said the Johnny English films to date have just been okay.
The character of Johnny English is basically a spy version of Inspector Clouseau. He is like the English version of Maxwell Smart. While I think Rowan Atkinson does a good job as the over confident yet blumbling character -- the film is just lacking something that could make it a better film. It has to be somewhere in the writing and tone of the films. Everyone around Johnny English is in a serious spy film where his buffonish character stands out in contrast. The Get Smart movie was similiar to a certain degree --but somehow pulled it off better.
The movie has some funny moments and was enjoyable at times --but isn't memorable. The Austin Powers films stand out to me as the best in the spy spoof genre. The tone of the those movies is consistent and most of the characters are just as absurb as Powers himself (Especially Dr. Evil). I think maybe the Johnny English films could have benefited from having the character in a world more suited for him. The serious spy film universe that the character bumbles around in just doesn't provide the consistent laughs that the Austion Powers world achieves.
A third Johnny English film is currently in the works for release this year.