Facebook has taken over from iSpot and you only have to go there to see why. Hugely active sites for all the different insect orders, with many experts there to give IDs and advice and all done in a very positive, encouraging manner. I know some people have concerns about using facebook, but it is absolutely fine and undoubtedly the place to go for insect IDs and more these days. It is so simple to add photos there and you get almost instant answers to queries. There are also files sections for each group, packed with ID keys and all sorts. For hoverflies, soldierflies, blowflies, general diptera it is the place to be. Same for beetles, bugs...etc.
A shame to have to say that, but I am afraid iSpot has been left lagging far behind. I still do what I can here, but most of my time is given to facebook now.