Advice on transferring yahoo email to gmail?

Anyone gone through the process of changing email addresses, and have any helpful tips?

I have a yahoo account that i've always used for pretty much everything (business, bills, friends, etc.), so i've been super hesitant in making the effort of actually transferring everything over. however, given the recent news i'm ready to act.

my main issue, aside from updating every fricking account or service i use with a new email address, is that i have 100s if not thousands of saved emails on yahoo that i'd like to transfer over, and i'm wondering if anyone knows of the easiest most secure way to go about doing that.

also, i'm open to other email companies. doesn't have to be gmail.

and finally you yahoo.