Posterous: posting via email and it sends it out to multiple sites at once. - cecily

Posterous is better for pushing content everywhere, and the commenting and favoriting system works better. - Kamilah Gill

Posterous! They are constantly working to integrate with different systems and dead simple. Tumblr is similar but doesn't keep my attention with features the same as Posterous. - Nakeva Corothers

Posterous: ease of use. - nakachi

Tumblr. Cuz I saw it before I saw Posterous. - Steven Perez

I've been thinking about moving to Posterous. I use Tumblr right now, though. - Jason Huebel

I'm still weighing them. but I'm using Posterous almost exclusively right now & autoposting everything to tumblr. - jbrotherlove

posterous, cleaner simpler interface, & very similar functionality in terms of media - sofarsoShawn

Hmm, seems like posterous is gaining a lot of traction. Can you map it to your own domain and theme it? (Like I have my tumblr right now at tumblr.the-frame.com and it matches the rest of my site like it's part of it.) - Jandy, ConcertMaven of FF

I need to look more into posterous - Shey, Jamaican of FF from iPhone

Jandy, Posterous supports Tumblr themes. - Vezquex: God of FF

And Jandy, yes, you can map your own domain. Glen Campbell's is an example. - Micah Wittman

http://twiddle.me - Glen Mistletoe

And there you have it :D - Micah Wittman

I guess guys talking about ease of use... it can go either way: Posterous - email update is so straightforward; Tumblr - if you login to post, it's got templates for you, e.g. quotes, videos, photos, which is actually a lot nicer than just an HTML email interface. I use both but I did think of keeping just one of them... Well, if that happens, I'm leaning towards keeping Posterous. - Jackie

Both: Posterous for broadcasting to other sites/services, Tumblr for sharing directly on Tumblr with the ability to monetize via Google Ads, affiliate ads, etc. Tumblr allows for great flexibility with adding html to your Tumblr site. Until Posterous allows for some sort of monetization of my content, I will be pointing visitors to my other sites and simply use Posterous as a broadcast tool to deliver content to those sites. - Louis Trapani

both! love posterous because i can post to a single address via my mail and tumblr because it holds things differently but these two can't replace my wordpress and blogger :) - ffcode

@Sanat, sure if you are Guy Kawasaki. Whenever I tried to add any customized code (i.e. Google Ads) it was stripped out of Posterous. - Louis Trapani

Uhm, posterous because I always forget about tumblr even though i've had it for longer. Oh yeah! And posterous posts to other places. - Adrian Scicluna

Posterous takes care of tumblr for me. - Rohit

For me actually both - M F

cant compare. for me, they are totally different tools and i love both. - browneyes

Two different services..! - ★ Soner Gönül

Tumblr. Posterous can't post "javascript:" links. - LouCypher

I would prefer Tumblr but for their bad SEO. I had the Tumblr blog for quite some time and it doesn't quite come up in search results. Posterous on the other hand, comes up though I started having it just recently. I really wish Posterous makes posting from their web interface as good as Tumblr. - Pavan

Posterous. Simply because it makes transferring those sudden thoughts to web pretty simple. Posterous is more about quick babbles. Tumblr is more formal. - Amit

Expanding on my previous comment: Tumblr, because I can post by e-mail (separate e-mail addresses for each Tumblr you create), sharing to Twitter, Facebook and FriendFeed; posting by IM via AOL IM; sharing on my website with a bit of HTML code; and I can call in audio posts; sharing comments with Disqus; and a nifty little bookmarklet that is a lot more versatile than the FriendFeed bookmarklet. Oh, and I like blue better than gold. - Steven Perez from IM

posterous - look at what I can do modifying standard template in a easy way: http://naturewild.posterous.com/ - storvandre

Posterous is easy. Tumblr is hard. I've loved using Posterous so far. - Mike Nayyar

Everything Posterous can do Tumblr can do better. Have people who say Posterous is easier to use used Tumblr? I don't know how you can make it easier than allowing you to email your posts or giving you a text box. - Mark Trapp

I have both, but I use Tumblr. - Steven Perez from IM