I had also been looking into some of the on-line courses available. I liked the look of the Paul Gilbert school from +ArtistWorks. I like Paul's teaching style. They had some special offers at the end of the year, so I treated myself to a three month subscription that started last week.
The school consists of lots of lessons grouped as Fundamental, Intermediate and Advanced. In his introduction Paul recommends that everyone work through from the start and I can see why. He includes lots of good tips in each video that are applicable to most players on basics like tuning and holding the pick. The latter is different to what I have always used. He uses his thumb and two fingers. I'm giving that a try and finding that I need to use a lighter pick to get smooth strums.
Fairly early on he introduces muting, which is a vital skill for electric guitar. Some of the exercises are fairly tricky, e.g. playing left-hand muted strums between each note of a pentatonic scale.
One of the big selling points of this site is that the instructor will give feedback on videos which you submit for specific lessons. I've sent in my first one and have another ready. I used Cheese to record the first one, but then had to convert the video (using Handbrake) to a format that they accept. GUVC offers more options, but I still had to convert the file. This is my second video. I can't send it in until Paul responds to the first. That seems to be taking a while.
I can't post Paul's response as it's locked into the site, but if you join then you can see all of them. He gives different suggestions for each person, so that makes for a lot of extra material to learn from. It's actually overwhelming how much there is.
The site has various social aspects including a forum and 'shout out' board that Paul participates in. There are also some interviews including this one with Dweezil Zappa. The whole thing is eight parts and they cover a lot of ground.
There is a free acoustic school you can join to see how it suits you. This is fairly basic stuff and I have only looked at a few of the early lessons. There are lots of other schools for different instruments and genres. Everything from classical to bluegrass.
ArtistWorks has an affiliate scheme. If you join with this link then we both get a free extra month. I think the prices are pretty good as you are only paying the equivalent of one private lesson each month.