Having been a member of EBay almost since it first began, I can certainly vouch for the fact that it's not what it was. It's now very much more complicated to search for things on a genuinely international basis from the UK or to search for things from within the UK without getting spurious listings from China and Hong Kong! The diversity of what's on offer also seems to be much narrower, probably because it's now much more hard work to go on and to make a listing.
P50 is right though about the mega rare stuff. Ebay's greatest strength has always been making it much easier to find obscure or mega rare stuff, usually where the interest and the market is very parochial. I used to buy stuff mainly from the USA, New Zealand and Australia where at the time there was literally no market for it. Perhaps I've been lucky, but in the 13 years or so that I've been using EBay, I've only ever had one serious problem with a purchase, as the vendor wouldn't admit to being at fault I took that to arbitration (Ebay's resolution centre) and eventually got a full refund and an apology. However I've also had rare, fragile items sent to me from abroad wrapped only in brown paper where I've still had no idea how they've made it through the postal system in one piece! Most vendors seem a little bit more professional these days or perhaps bubble wrap is easier to get hold of.