For sure. For perspective, that's around 2000X more than an average tech salary in Silicon Valley. I'd be thrilled to [Not Turn Around Yahoo] for that much money. Hell, I could have done it for a fraction of the cost!
London may be in a class of its own, but elsewhere in the UK £35k is considered decent money.
That said, a "Web designer" role and a "Developer" role are two completely different things. £35k is about right for a decent web designer salary; but for a developer, that's more of junior to mid-level role, even outside of London.
Compare http://www.itjobswatch.co.uk/default.aspx?q=developer&l=&id=... and http://www.itjobswatch.co.uk/default.aspx?q=web+designer&l=&...