I'm a 15 year veteran smoker & a 1 year+ grower so I could probably give some pointers. I do agree with an earlier post that it affects everyone differently, but there are some general things. I want to also note that these side effects are very mild & often the benefits of herb usage outweigh the negatives.
Short-Term Memory(only with regular use...if you stop for a little it will come back)
Pyschological Addiction(other then trouble sleeping when you first quit smoking after awhile there are no distinctive physical symptoms I've noticed)
Economic Lack Of Concern(ex.- You buy herb before you pay certain bills)
Finally I've noticed that Cannabis is such a mind opening substance that it can cause difficulty dealing with society...what I mean by this is that you often will find that regular users are extremely dissatisfied with society & kinda don't fit in. This is simply a result of the unbalanced world we live in...like NewGrowth said "Herb tends to balnce" in my opinion.