My wife and I lived in Finsbury Park for a little over a year when I first moved to the UK in 2007, and we really liked it. We lived on a side street that backed onto the Parkland Walk (former railway that's now a nature walk) and Finsbury Park (the actual park) on the other side of that.
There are parts of the neighborhood south of the tube station down Blackstock Road that seemed a little rough, but if you go north of the tube station up Stroud Green Road it gets progressively nicer. It seemed to be gentrifying; I haven't been back recently to see how it's changed since 2008.
There were a number of pubs within walking distance, one of which (the Faltering Fullback) has excellent and cheap Thai food. We also liked CATS, another Thai restaurant, and Pizza Pappagone is the best Italian food I've had in the UK. There's a Tesco Express that's big enough to do your regular grocery shopping, and a couple of little Kwik-E-Mart type places in the area, a butcher, a hardware store, several barber shops, and a couple of little funky gift places.
The transport links into the rest of London are great, with the Victoria and Piccadilly lines at the tube station, and a decent range of busses, too. All the housing is row houses that have been converted to apartments, and our one bedroom place was £900/month.
We eventually moved out to get a place in the countryside (my wife is a country girl at heart) with outside space.