Everyone keeps ooo-ing and ahhh-ing over Sludwig's bird, but I greatly prefer Mark's design from the contest anyway. Sludwig's bird looks like it has shag-carpet-feathers syndrome, and that makes it look too much like Thunderbird's bird.
The reason people "ooo" and "ahhh" about Sludwig's proposal is because they like it. It effectively builds on mark's design. Some people think it's better, some don't. Personally, I think they both have their own ups and downs.
Sludwig's proposal scales exceptionally well, far better than mark's. That's what caught my eye. However, mark's logo has been in the works for much longer, and has therefore had more time to develop. Sludwig's bird is, perhaps for that reason, not (in my opinion) as good as mark's at 128x128, for instance.
As for the shag-carpet-feathers, that's one of the feats that make the TB-logo better than the current Sunbird logo. The sunbird logo just looks too plain. Sludwig has improved this, I think, as well as adding some consistency in the art style.
How does it matter that Sludwig's proposal is the current logo's "cousin"? Family has to stick together and learn from each other's mistakes, anyway. The only negative outcome of Sludwig entering the stage would be if the artists that have all produced outstanding work for this contest (Mark, Suslik, Sludwig, Jeff) can't work together like a team.
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