Swimming as an only source of exercise

Hi All, I am new to swimming (my swimmer wife and son both tell me my form is horrible, etc) but I absolutely love it and I feel like it is one of the most complete workout routines Ive ever done. I am working to increase my training times, distances etc and I am really feeling the burn in my muscles but its the good kind of burn you get when you know things are heading in the right direction! What I want to know is if I keep swimming will I see some good results in terms of getting slim and trim or will I need to incorporate other dry-land exercises into my routine? I know it wouldn't hurt but if I can get through with doing my entire exercise through swimming I want to go that route. Just curious if anyone has any transformation stories or input on this subject. I look forward to anything you can add. I feel like Ive found a new avenue in my life for staying in shape and I dont know enough other people who swim to talk about it with anyone. Thanks ~J