Absolutely every mangaka's art goes through a transformation as the years go by. Some are VERY drastic and for the better (Kodaka Kazuma), some are more subtle, but still noticeable, as is the case with Nakamura Shungiku. Unfortunately, there are some mangakas whose art becomes of poorer quality as time goes by. (Takatuski Noboru) I really don't understand how that works.
It IS an improvement. A very much appreciated one. :)

been reading this for a very long time and it made me realized something...takano's face is no longer squarish long...it's now even more finer with no edges...while onodera's, there are some changes too...well it cant be helped if the art style is having progression... what do you guys think? :D