Windows 7 - Article from 2008 that needs a revisit

The Windows registry is a massive database of almost every setting imaginable for every application on your system. It only makes sense that cleaning it out would improve performance, right? Sadly it's just a marketing gimmick designed to sell registry cleaner products, as the reality is quite different... registry cleaners only remove a very small number of unused keys, which won't help performance when you consider the hundreds of thousands of keys in the registry. This isn't to say they are completely useless, of course. I'd still recommend cleaning the registry when you are trying to troubleshoot a problem caused by uninstalling buggy software that leaves entries behind, but even then you should be very careful to use a reputable application like previously mentioned CCleaner and review the entries before deleting anything.
Ed Bott weighs in with a stronger opinion:

I’d go a step further: Don’t run registry cleaner programs, period. I won’t go so far as to call them snake oil, but what possible performance benefits can you get from “cleaning up” unneeded registry entries and eliminating a few stray DLL files?

Make Vista Use Multiple Cores to Speed Up Boot Time

This bogus tip made the rounds recently and almost everybody got caught including Lifehacker and big brother site Gizmodo... although commenters called it out quickly on both sides, and the editors updated the posts. (That's yet another reason to always participate in the comments here.) According to this tip, you were supposed to use MS Config to modify the "Number of processors" drop-down on the Boot tab. The problem is that this setting is only used for troubleshooting and debugging, to be able to determine if there is a problem with a single processor, or for a programmer to test their code against a single core while running on a multi-core system. Windows will use all your processors by default without this setting.

The browser service maintains a list of the domain name or workgroup name the computer is in, and the protocol being used for each computer on the network segment being served by the computer running the browser service. On each network segment, a master browser is elected from the group of computers located on the segment that are running the browser service.

Tablet PC Input Service

Isn't that the one that makes the snipping tool work in Vista? I think in Windows 7, it is no more required for the snipping tool to work. That was a funny connection anyhow.

This indeed a good reminder. Many people still believe in this registry cleaner myth. And Ed Bott is a pretty good authority in those matters. I would be interested what people like Mark Russinovich would say. Maybe someone who has access to him can find out.