I don't know how much my opinion counts as I am still a newb myself but I have used both programs and I personally like GIMP. It's not all that difficult to learn to use and although I haven't looked at any of the tutorials I didn't really need them. (I am the type of person who learns by doing as I can't learn as well by reading)
As far as photoshop goes, I've used it extensively for my graphic arts classes but I have to tell ya, if you don't have a lot of RAM you can't really play around with images as much as you might like. With GIMP you can play more. I think it has to do with the amount of system resources tied up when you simply open PS compared to gimp.
Try them both out and see which you prefer... you can download a free trial of PS before you purchase it if cost is an issue.... I know it's quite pricey especially if you get into all the add-ons that are available.
ttfn
CDL.