First off good news, Tumblr is working! Bad news? It's not yet implemented on the site. This is because unlike Twitter and Facebook, Tumblr doesn't officially support a login feature for users.
Technical Stuff :)
When you use Twitter and Facebook you obtain the same credentials every time which can then be compared to our database to initiated your login. This is very secure since all information is directly requested from the provider so even if
another person obtained your key, they wouldn't be able to use it. However, because Tumblr provides a new set of credentials each time, an extra step is required to check login. Being your Tumblr User ID. Basically, it requires an extra step.
If there is no problem with this method than I'll likely include Tumblr as a login on feature. The only downside is it's an extra step which will make the login process about 1-2 seconds slower.
Because tumblr login is not included yet there just isn't a reason to add it! Plus I want to add an extra step before I make a decision if I want to include Tumblr login or not.
So now onto the exciting updates! Since the last update I've been rewriting all the code for the login library. It's now A LOT cleaner and easier to use. This means adding future providers will be a snap. But because this is a behind the hood update you won't
notice any changes.
But don't worry, there will be a lot of neat features coming your way in the near future.
Until next time!
~Webmaster
Update: There looks to be no rate limits with the Tumblr API and it's not against the TOS. This means Tumblr login is very likely to happen.