Do essay topics change a lot from year to year?

[hcueva]

I'm planning on applying this fall, to enter in 2012.

Since I already took the GMAT, I don't have much to do anymore... I understand that next year's essay topics will most likely be released in June or July, is this correct?

Also, should I expect most essays to remain more or less the same, or would it be a waste of time to start working on this year's essays? (Harvard, Stanford, etc.)

[humblebee]

I can tell you about my limited experience with this

HBS - Pretty much in the main stays the same from year to year. Only the secondary essay questions changed
Stanford - Questions stayed the same from last year
Wharton - They completely changed their primary question. It's hard to say if they'll change it again.

If you wanted to work on your applications now, your best bet is to

1.) Formulate your overall positioning strategy i.e. how you want to sell yourself, your personal brand
2.) Write your goals essays (these are asked by every school except for MIT)
3.) Research the little nuisances about each school you apply for