That's from the week when Vista was first released. They would have tested the RTM version of Vista with really immature drivers. Vista graphics drivers have improved a hell of a lot since then. Irrelevant.
1GB of RAM for Vista? One thing I will give you is that if you have 1GB RAM, upgrading to Vista is a bad plan.
Anyway, all that says is that Vista took 20 seconds longer to start and used a bit more pagefile, on a rig with 1GB of RAM. Oh, and was 3% slower in a benchmark. Not exactly damning.
That isn't relevant either - it compares Vista RTM to Vista SP1, and XP SP2 to XP SP3. It doesn't give any results comparing XP with Vista.
This is interesting. All of these refer to the same survey, done by a company called Devil Mountain Software. The link above from Mobile Computer Mag is a survey done by 'exo.performance.network' - which, if you google it, is a project from Devil Mountain Software. I'll have to look into it a bit more, but the company doesn't seem to have done anything but bash Vista. Also, their claim is pretty extreme - they claim that XP is more than twice as fast as Vista. Curious.