1. they do both demand skills, but it takes more skill to make a piece from scratch that can appeal to the public eye, than to make a piece that uses something that is borrowed. if you read my first post (page 2 of this topic), you would see that i already said that it takes skill to make a piece, even if it is not from scratch. I also said that i don't consider sigs/tags to be "true" art, meaning it is a form of art, but not at it's purest state.
i think its art in some way. but, i hope the creator of the tag doesn't feel so "proud" of his creation, considering he used stocks, brushes etc from other peoples sites and what not. and making a portrait of someone is considered very arty in my eyes.. it isnt just getting a photo of someone, placing it on the paper and colouring in the background. take it the same way when you get your renders, you don't draw/paint the picture into your tag, you drag it onto and and use it from there.
ART –noun 1. the quality, production, expression, or realm, according to aesthetic principles, of what is beautiful, appealing, or of more than ordinary significance. 2. the class of objects subject to aesthetic criteria; works of art collectively, as paintings, sculptures, or drawings: a museum of art; an art collection. 3. a field, genre, or category of art: Dance is an art. 4. the fine arts collectively, often excluding architecture: art and architecture. 5. any field using the skills or techniques of art: advertising art; industrial art. 6. (in printed matter) illustrative or decorative material: Is there any art with the copy for this story? 7. the principles or methods governing any craft or branch of learning: the art of baking; the art of selling. 8. the craft or trade using these principles or methods. 9. skill in conducting any human activity: a master at the art of conversation. 10. a branch of learning or university study, esp. one of the fine arts or the humanities, as music, philosophy, or literature. 11. arts, a. (used with a singular verb) the humanities: a college of arts and sciences. b. (used with a plural verb) liberal arts. 12. skilled workmanship, execution, or agency, as distinguished from nature. 13. trickery; cunning: glib and devious art. 14. studied action; artificiality in behavior. 15. an artifice or artful device: the innumerable arts and wiles of politics. 16. Archaic. science, learning, or scholarship. [Origin: 1175–1225; ME < OF, acc. of ars < L ars (nom.), artem (acc.)] Definition of art is above, now I think tags play into that.