I have 194. I've been collecting since 1999 (when Pin Trading became official), though some of my pins are considerably older. One is from the 15th anniversary of WDW (1985). 93 are limited editions. My lowest edition number is a set of 250 from Disney Auctions. 21 are cast member exclusives including a completed set of the Character Hats collection. 1 is from Tokyo Disney. 5 are from
Disneyland Paris/Eurodisney. 1 is a Disney Studios pin from Burbank. I have 2 pins signed by the designer. I have probably 50 Annual Passholder exclusives and DVC exclusives, though those aren't hard to come by considering we have both. My most prized pins include a Countdown to Extinction pin that we bought before the ride was renamed Dinosaur, an Alien Encounter pin from before it was converted to Stitch's Great Escape, a Disney Club pin my mom got for joining (the Club no longer exists), and a Disney Club Megavolt (the villain from Darkwing Duck) pin- it's the only Darkwing themed pin I've ever seen.
Overall, my collection is probably worth over $1000.
I do trade, although not my collection pieces. I trade for new ones. I get a bunch of pins for relatively cheap on EBay (and I check to make sure that they're not fakes) and I trade them for duplicates and such with cast members and new pins for my collection. The duplicates I usually haul to DTD and hit the pin traders there and sometimes my duplicates complete one of their collections and they're willing to trade some really cool pins for them. But really, I've never met a nicer group of traders than the ones at DTD. Some of those people have tons of pins and if you see one that you really, really want they usually let you have it for a really dinky pin (like an open edition Alice pin). That's how I got my Mad Hatter's Hat pin (complete with Hat Box!).
My major collection is cast series pins (like the Wanted Posters and the Hats before I finished that set). I have 4 unfinished sets right now that I hope to complete sometime within my next 2 trips (august and december). I do however, have a secondary collection of all things Alice in Wonderland.
I need to remember to buy more locking pinbacks in august, too.