GuideGuide is for advanced guide placement and for grid management. Last I checked GIMP didn't allow for automation of guide grids.Plug-in not needed. Its standard. But there is an alternative.
You're lazy, aren't you? A plug-in to tell you if you're using web standard fonts & allows you to mock them up? Really? ..... Don't worry, we've got you covered.
Seems like a dropbox service... cloud service. There is an option (or plug-in) to share. Got you covered. And its free too.
Another cloud type service if I understand correctly. If Cloud is where you're going, then yes, Photoshop's monthly fee is what you should be paying. Good luck with that. My point was GIMP was good enough as a stand alone (to replace Photoshop) & best of it's free
There is a plug-in for that.
Got you covered too....
You don't say?
WebInk allows you to use commercial fonts, or Google WebFonts without installing them manually (Same goes for Fonts.com). This is obviously a huge asset when you're doing a mockup for a client and need to show them different typography when you do not currently own the fonts or a subscription to one of those services.
PixelDropr is great for when you're creating or using a UI kit for large projects. I'm making a XenForo kit so that I can mockup designs for add-ons quickly without having to constantly re-creating elements.
All of these are for productivity so saying that it's lazy to do so is rather stupid as productivity is cutting down on erroneous tasks that can be completed in a faster way. When you're working at a large scale just cutting out a few tasks will save you a ton of time and effort.
GIMP isn't good enough to replace Photoshop. It is a good substitute for hobbyists, dabblers and beginners but cannot ever replace Photoshop in any shape or form. It doesn't offer enough in the way of productivity or functionality out of the box and the use of plugins doesn't necessarily negate that.
You also can't have it both ways. If GIMP can use plugins to offer functionality of Photoshop, Photoshop can use plugins to offer additional functionality which GIMP doesn't offer .