Tough call, the 35-70 has excellent color, is an excellent portrait lens and better range than 18-55 for portraiture. Like Don said, sharpness test, the 35-70 is certainly better than the 18-70 kit I got, bu the new SAM 18-55 is a lot better than that one.

At least, the 35-70 is a constant f/4, which is marginally faster and marginally more convenient to meter off of. Alas, 35mm is a terrible starting wide for a lot of general purpose. My guess would be - 18-55 for general use, 35-70 for portrait and more specialty.

Get yourself a 50mm f/1.7 too, best starters lens in my opinion.