Just a request, and maybe this is useless for most people, but..
For people who's screen size isn't as big/bigger as full 720p (which is 1280 wide).
I like the 720p option, but sometimes videos are just TOO big.

My resolution is just slightly smaller, width wise, and as a result, the edges of true 720p videos get's cut off by the screen.
I propose an option called "Fit/shrink to screen - 720p Only" or something like that.

The reason this is better than normal "fit to screen" (which stretches all HD videos to screen size) is because some of us don't like seeing all videos in a stretched format, which can cause blurring or other ugliness.
I just prefer to see all videos in their true-recorded size, for the most part, except videos that are larger than my screen.

Again, maybe this is redundant, or maybe I just don't have a proper understanding of these options, but I think this would be useful. Either way, just a suggestion.

Thanks for a great script! Can't watch YouTube without it!

I never used True 720p because of this reason. Your post got me interested in solving the problem, so I did. I changed the code so if you check yes to Fit to Window and Big Mode, it will only go Fit to Window if it's HD. Everything else will stay in Big Mode.

Here's what I changed.

if(opts.fit) {
fitToWindow();
unsafeWindow.onresize = fitToWindow;
}

to

if(opts.fit && unsafeWindow.isHDAvailable) {
fitToWindow();
unsafeWindow.onresize = fitToWindow;
}

hmmm, Well that's not exactly what I meant, but it does do the job anyway.
Frankly that's probably how Fit to Window should have been in the first place (since it claims to be for HD only, but normally stretches everything). So nice job with that, it's almost like you fixed a bug!
Basically, this makes the 720p option useless to me now, which is fine.. Since I can finally use Fit to Window without stretching non-HD videos.
Thanks a LOT for that! =)

BTW, with your edit, you don't need to enable Big Mode, as long as fit to window is enabled. Try it yourself. It's not just me, is it? One less option I need enabled, I guess. lol
Your small edit couldn't be more perfect!

Yeah I understand that. I guess my problem was more with "Fit to Window" not working exactly the way I wanted/thought it should. Which isn't to say there's something actually wrong. Just personal preferences I guess.

My monitor is almost big enough for full 720p videos, but that option was behaving oddly to me.
Turns out I really just wanted an 'alternative' Fit to Window mode.
So BCBomb47's edit works great for me, and I've been using it for a couple days now. You should try it out. It's quite nifty, and it's the only size related option I need enabled now!

Anyway, thanks for a great script, I simply can't live without it! And your latest update is even better! Very nice loop-toggle button!

Thanks NikoKun! Glad you like my edit. I had always kept Big Mode on, so I never noticed that I could turn it off and it would still work. lol

One thing that bugged me when I made my change was that normal videos wouldn't be centered on the screen anymore. Could be my OCD but I didn't like it. :) If you want to fix that here's what you need to do:

Change:

function fitToWindow() {
	player.style.marginLeft = (window.innerWidth >= 960 ? Math.floor((985 - window.innerWidth) / 2) : "0") + "px";
	player.style.width = (window.innerWidth - 20 ) + "px";
	player.style.height = (window.innerHeight - 53) + "px";
}

to

function fitToWindow() {
	player.style.marginLeft = (window.innerWidth >= 960 ? Math.floor((874 - window.innerWidth) / 2) : "0") + "px";
	player.style.width = (window.innerWidth - 20 ) + "px";
	player.style.height = (window.innerHeight - 53) + "px";
}

and

if (opts.fit || opts.true720p)
	GM_addStyle(".watch-wide-mode, #watch-this-vid, #watch-player-div {padding-left:0px!important}");

to

if (opts.fit || opts.true720p)
	GM_addStyle(".watch-wide-mode, #watch-this-vid, #watch-player-div {}");

Hope this helps! Now I just gotta figure out how to fix that stretched video issue.

Thanks again BCBomb47. Yeah I noticed it wasn't centered, but I didn't mind that since it was still attached to the left margin in a way that looked youtube-like. lol
I think I'll avoid making too many changes to the original script, too hard to keep track of, and too many possible errors to make, on my part. Thanks though. =)

--
Oh, and I can't wait to see what you have in store for us, Avindra!

EDIT(even if you don't see this): Just upgraded to v1.1.3! Awesome job. Sizes seem to be working fine, at least for me, and I don't need to edit the script or anything anymore either!
I hope we didn't give you too much work to do! lol