Intro is waste of time imo.

First 15 seconds of your video are crucial as there is a high drop off rate aka people stop watching your video after that so you have to wow them in that short time frame so if you have an intro make it impressive and not too long so they stick around and watch the rest of the video.

I got an intro, which is short and has an impact. I think it is a great way to express yourself and to seperate yourself from others. I'd say yes intro, but try to keep it short and if you can make an outro with a similar style. Try to look at mine as an example, so you get what I mean.

I have a short 8 second intro that I made in Adobe After Effects. The outro is the selling point though. Mine has video in video where I can display 3 of my previous videos along with subscribe/playlist/whatever buttons to annotate and such.

A well made 8 second intro is a great way to capture a potential viewers attention. I usually mix up my intro logo by making it themed on the game I am about to play like for MGS Rising my head had Raiden's visor slam together and for Batman I came together in a field of bats. It is a great way to show passion and professionalism of your channel.

I don't have an intro, but i do have a little channel intro, that people will see if they click on my page which is pretty good to get people to subscribe. I've noticed since I uploaded my channel intro I've earned a few more subscribers than usual

depends on what you're doing. More informational style videos I find an intro to work really well but only like a 15 second one, it makes you look like you know what you're doing and it looks professinal
for a basic let's play channel they're a waste of time, people usually come to see the person play the game and in this case your personality is far more important so do a spoken intro ala pewdiepie,markiplier,tobuscus etc. where you say a catchy line and your name and then straight to business.
For example, I'm Irish so I say "Top of da mornin to ya laddies" and it sticks in their heads

Intros less than 8-10 seconds is acceptable, but then your viewers will see that same 8-10 seconds everytime they start a video ^^. sometimes it does get annoying.

I personally just prefer when people do a quick talking intro to that specified video, they are super easy and take no extra effort, plus they make the intro more personable, as apposed to the same intro every video.

Intros bring a degree of professionalism to the video, but a poorly done one will probably hurt your channel.

I say absolutely yes to the intro, but make it quick and look good!

I think intros are fine, particularly since they can help people remember your channel. But I also think anything longer then 5-8 seconds is too long. People have a short attention span and will often click off your video in the first minute or so, particularly in the case of longer intros.

Yeap. I got 5 different intro for each of my different video but I only use 2. One is just MsgNinja Production and the other one is Minecraft Edition. So it is up to you if you want intro. My partnership say that I can use intro to bring in more views but like if that is true since a lot of my views hate intro but I rarely do it.

I use intros for my various video shows, i think it helps to differentiate between the different content. Though over time they have become shorter with some only 5 seconds long. Though my main documentary series still runs for 20 seconds as i took a vote and everyone liked it, so I remade it with higher quality footage instead.

Intro is useful only of it's REALLY, REALLY good and it must be short, about 10 seconds...
My personal opinion is that the intro doesn't make a very big impact on viewers criticism about your videos.

Just look at the big youtubers, a lot of them don't use intro, they just say hello and introduce themselves.

So if you ask me, I say no intro.

Personally I absolutely despise watching videos with intros.
You are not a TV show, what are you doing...?

Exactly, this is the best answer yet!

I think a short, 'sleek' intro is a good idea. I couldn't think of anything that I could possibly make myself in After Effects, so I searched for some customizable templates, found a decent one and edited it

A 7 second intro is something you despise vicsyyy? It is the first impression you can give someone to show you're different and interesting. To stand out you need to seperate yourself from the "big" youtubers. Even a 3 second intro can help a lot it is just important to represent yourself. And of course it needs to be good and catchy.

And in some way it indeed IS a show. Not a tv show, but still a show.