Only really with iPhones. It's killing me they came out with the 4S; I don't think it's worth getting over my 4(I don't want to waste my update, and think the 5 is much less than a year away), but at the same time I hate having last years phone. Yay first world problems FTMFW Before my 4 I had a BlackBerry Bold 9000 that I got the month it came out; aside from the new touchscreen/physical keyboard Bold that's around the 9000 form factor, it's still the best blackberry out, the formfactor and keyboard are amazing.
With iPods, I got a 1st gen Mini right when it came out in Jan '04, then didn't get another one until the end of '05 and got a 60GB Gen5. I did get a second 60GB when I did the iMod conversion, but that's just because I wanted to start with a new one, it was the same model. I did get a 1GB shuffle, but I don't even remember when that was, it was an impulse buy at BestBuy.
I got my first Mac in April 2010, the day the "mid-2010's" came out and got a 7,1 2.4GHz C2D. I've put in a Vertex3 SSD and 8GB of RAM. Nothing I do regularly is processor intensive, and when I was studying with my friend who has a 2011 15" with a HDD it was night and day how much faster mine was opening stuff and loading, so I'm very happy with my undervolted C2D. And it has no problem pushing full HD 1080p BluRay .mkv's(8GB-12GB+) to my 50" 1080p plasma (or any other of a number of HDTVs) through MDP>HDMI with audio. I still have AppleCare until 2013 so I'm keeping it at least until then, and will probably use it until something breaks once AppleCare is done then replace it with whatever the 13" pro flavor is at the time.