From what Ive heard, estrogen (and t-blockers) will make you more emotional. In many cases it will get easier to cry and to show affection. Ive also heard that many girls start wanting sex for different reasons than before (mainly for connecting with partner(s), because they are in love etc). I dont think its like this for everyone tho.
As for FtMs, Ive heard its common to get more aggressive, less sensitive, finding it harder to cry and show affection. Oh, and wanting sex more often and having it just because its sex. But, most people I know who are on T experience none or little of these changes.
some changes in personality/behavior wouldnt surprise me at all.