Há séculos que não actualizo isto...
Falta a pachorra, tempo e disposição. Mas, oh well, deixa por aqui um texto de um post/resposta que coloquei no twoplustwo e certamente será útil a muito boa gente (desculpem lá mas vai mesmo em inglês):
Q: Rakeback, how important is it
A:
First and before anything else: what really matters is not rakeback but the effective rake you end paying (rakeback is something they give you back from what you already paid and you do not pay the same everywhere!).
Ef.rake = Rake - Rakeback
For example: you may pay 1.5BB/100 at site A and 2.8BB/100 at site B for the exact same game and stakes. So, if you get 20% rakeback at site A and 40% rakeback at site B, you are in fact significantly better at site A in this matter of rake/rakeback.
Thats the first thing: dont look at rakeback solely, consider both things, the rake you pay at site X and the rakeback that they give to you and determine your effective rake.
Secondly, rakeback as a factor varies widely between games and stakes: you must consider how heavy is effective rake and how it compares with achievable winning rates at that game and stakes. There is no general rule. For example: rakeback tends to be much more important at Fixed Limit and specially at the lower stakes than in other formats, cause you pay a lot of rake at the tables (like 3BB/100 and even more) while even a good player will make something like 2BB/100. But then again, you may be playing NL at a stake where you pay 1.5BB/100 in rake and you may achieve 7BB/100 of winning rate. The relation is not the same and its not even close so rakeback is not as important for both these players. Sames applies to sngs where fees and winning rakes varies widely.
You have to look at all this things...
And then at softness, security, traffic (that interferes in table selection and number of tables you may want to play), etc, etc, etc...