I think that there is a grain of truth to some of it.... yet, the descriptions are so vague it is hard NOT to read some traits into my 'sign'. IMH dumbass opinion, I think it has more to do with the season of year one was born than stars. I just notice that people who celebrate birthdays in the late spring/early summer have a different outlook than those born when things are going dormant in the late fall. My anecdotal pithy story to support this: I am a Gemini (mid June) so the start of my life is associated with early summer. Those vague Gem traits like spontinaity, hyperactivity and the drive to 'do it all' are very true in my case...but after a northern hemosphere winter...who isnt? I have an Argentine cousin, about the same age, whos birthday is December 15th...the southern hemosphere's late spring/early summer....and his personality is allot like mine.
As adults, our birthdays are more like, "oh goodie, another year" event...but as children it is a big deal...and I think that the time of year has some impact on our personality development.