I've been using Retin A for the past 12 years (since I was 30). It is drying and can make your skin sensitive. You must wear sunscreen every day if you use it (but you should do that anyhow). I think it has done wonders for keeping wrinkles at bay, evening my skin tone, and giving me overall a very good complextion. I am 42 and often am told that I look closer to 10 years younger.
That said, you do have to watch what other products you use w/ it. I find that other "antiaging" creams are too irritating, as are most facial washes (I use Ultra Bland from Lush). I wear a pretty heavy moisterizer at night, during the day w/ sunscreen, and often reapply during the day. I also do not use the Retin A every day, particularly in the winter. Many people use Cetaphil or similar cleansers and mouisterizers when they use Retin A.
I have never heard of it causing wrinkles. There are so facial changes that happen due to loss of muscle tone under the skin, and I dont think there is anything you can put on your skin that will prevent that. Retin A does what a derm peel would do whereas the muscles woudl have to be fixed w/ a facelift.