What if Jakob Nielsen had a blog?

Location is Irrelevant for Usability Studies

As long as you're testing within a single country, there's no reason to expend resources traveling to multiple cities and conducting the same usability study again and again. You'll simply observe the same behaviors repeatedly, and learn nothing new. Better to save your budget and spend that money on new tests of either additional design ideas or your competitors' designs.

This conclusion -- that the test location doesn't matter -- is different than the usual lesson from market research, where you find different results in different regions of the country. It's therefore common to conduct focus groups in 4 to 5 cities, or more if the budget allows.

Because traditional wisdom recommends conducting research in multiple locations, we've done so for many projects over the years. But, except for the few special cases discussed below, we've always identified the same usability findings, no matter where we tested. By now, we can clearly conclude that it's a waste of money to do user testing in more than one city within a country.

http://www.useit.com/alertbox/user-test-locations.html

Show Numbers as Numerals When Writing for Online Readers

As an example of the latter, if I say something like "in recent years, we have tested thousands of users and seen their use of breadcrumbs increase," it's better to write "thousands" as a word than to write "1,000s" or something like that. "Thousands" is not really data in this context, it's intended to give an idea of the scope of the research. On the other hand, it's better to use numerals when stating the exact number (e.g., "we have tested 2,692 users"). Disclosing the exact number also increases the statement's credibility.

http://www.useit.com/alertbox/writing-numbers.html

Breadcrumb Navigation Increasingly Useful

Breadcrumbs won't help a site answer users' questions or fix a hopelessly confused information architecture. All that breadcrumbs do is make it easier for users to move around the site, assuming its content and overall structure make sense. That's sufficient contribution for something that takes up only one line in the design.

Breadcrumbs have always been a secondary navigation aid. They share this humble status with site maps. To navigate, site visitors mainly use the primary menus and the search box, which are certainly more important for usability. But from time to time, people do turn to the site map or the breadcrumbs, particularly when the main navigation doesn't quite meet their needs.

http://www.useit.com/alertbox/breadcrumbs.html