Having played the guitar for over 15 years in many different bands having made recordings and taught many students the guitar I have noticed that there is one thing that separates a good guitar player and one that needs work. It comes down to this one essential aspect of guitar playing that makes all of the difference, and that is rhythm. You may think that you have a good grasp on your rhythm but there may be some room for improvement that you can make that will improve your playing.
Natural talent vs Hard Work
It's true. Some people are quite simply born with more musical talent than others, that is why it is called musical "talent" not musical "skill", because it isn't learned it just comes naturally, and to some quite easily. When it comes to rhythm it can be mastered in one of two ways, natural talent or hard work. If you are fortunate enough to have a good portion of musical talent than you will find that it still takes work but just less of it. If you aren't a natural prodigy than the good news is that you can compensate with a lot of hard work. I have seen many students who weren't rhythmically gifted close the gap between them and their more talented peers through sheer hard work and determination. So if you are looking to improve your rhythm skill it is time you became better acquainted with the good old metronome. ( I am sure that you have heard of a metronome before, but just in case you are unaware a is a simple piece of machinery that keeps time. You can purchase one at your local music store or on Amazon.com *wink wink)
The problem with using a metronome is that it is quite simply boring, and this simple fact is what keeps many students from using this tool, it just isn't very fun. Guitar, is like anything else in life, you get out of it what you put into it. If you ever read about successful sports stars they will usually talk about how they improved their skill by constant repetition. Whether it is running plays at a football practice or doing scales on the guitar, these rudimentary actions are boring, but they improve skill. This is an advantage for anyone who wants to be a better guitar player, or do anything better for that matter. Make a habit of running through the basics, use the metronome to play along with and also play along to your favourite band. When you improve your rhythm your calibre of playing goes to a whole new level. If you are looking to increase your skill but don't find it feasible to get a guitar teacher I would recommend a product called Jamorama, which is an electronic guitar teaching method. I have never used it myself but I have looked it over and it appears to be pretty high quality and looks comprehensive, especially for the price. It doesn't cost more than a couple of lessons with a teacher.