I feel as I grow older (I'm 36), the variety of aircraft I see is diminishing. Or at least the new ones just aren't as beautiful as they once were.
Back in the 80's, I went yearly from SAN to MKG via ORD. Most times, we flew in an Air Wisconsin De Havilland Dash 7, hence my username. I'm kind of sad those don't exist in america anymore. I loved it as a kid. Antiquated now, but most of the fun aircraft are.
Last Monday, on the Weather Channel, I watched Ice Pilots NWT, which I had seen on YouTube. It has come to America. I rather like the show, and LOVE seeing the DC-6 flying. There's something rugged about it, and that's not a word I usually bestow on an airplane. It's just very industrial-looking, and has a great engine sound.
As for modern airplanes, I still love the 747, but also am increasingly aware that it will be phased out somewhat soon (Y3?). I also find the Dash 8 Q-400 very sleek. In fact, Alaska is unveiling an SDSU theme logo for a Q400 down at SAN on Thursday at 10 or 10:30. I'm planning on going.
Private planes never excited me much as a kid, but I'm getting somewhat more interested. There's a new (?) class of plane called a VLJ, or very light jet. Some of them are really sleek looking. I like the Eclipse 500, though I think that company went under.