Published: October 14, 2012 at 1:17 PM
It really depends on several factors, the most important of which are how far I have to travel to visit the park and how major the addition is. For local parks (the seven major Southern California parks, all within a two hour drive of me), if it is an E-ticket, roller coaster, or record breaker, I'll make a trip to ride it some time during it's opening season. I will usually wait at least a month just in case there are bugs with the ride and to let the crowds die down, unless I have a pass to the park. If the new attraction is not a headliner and I don't have a pass, I usually just wait until my next visit.
Here are examples for the new for 2012 attractions in my local parks:
Cars Land (Disney California Adventure Park): Openend in June, I visited in September. This was both due to pass blackouts and to avoid insane summer crowds (no ride in existence is worth more than a two hour wait, not even the best ride on Earth).
Transformers (Universal Studios Hollywood): Opened in May, I rode in June. Normally, I would have waited a bit longer, but since July was booked, my pass expired in Mid-August, and the ride had been soft-opening for around a month I decided to go as soon as school got out.
Manta (SeaWorld San Diego): Openend in May, I rode in August.
Lex Luthor: Drop of Doom (Six Flags Magic Mountain): Opened in July, I haven't rode yet. I've learned to not trust SFMM's opening dates after they missed announced dates on both their coasters last year, so I would never plan a visit to this park until I knew the ride was running. Additionally, since I didn't get a 2012 pass but am getting a 2013 pass, I decided to wait until they were available before visiting (currently, I'm planning to go in December to try this one out).
Pirate Reef (Legoland California): Opened in May, I haven't rode yet. Since this is not a major attraction, I have no current plans to visit the park (I just visited last year), but will ride it next time I do visit (usually I visit Legoland every 2-3 years, so I'll probably be back in either 2013 or 2014).
For parks outside of Southern California, I won't plan a trip to visit them just becuase they got a new ride, but I will put them back on my park visit priority list if the attraction is major enough (for example, I haven't wanted to go back to Cedar Point since my visit in 2008, but GateKeeper is enough for me to add it back onto my list). I still usually prefer to visit new parks over return visits, but as long as the park is on my list I'm interested in visiting again.