I noticed that XP isn't a hot topic on this Wiki anymore. I had a few spare minutes so I did a little research on the web. Here's some data on the number of web hits using the exact search phrase 'extreme programming'. The first column is the half of the year (first half, then second half). The second column are the usenet articles from that date range. The remaining columns are the web hits for all the web, the gov domain and the edu domain. Of course the web hits are going to be more of a cumulative measure, while the usenet hits are really date-specific. Draw your own conclusions!
date usenet web gov edu
1-97 9 0 0 0
2-97 8 3 0 0
1-98 29 10 0 1
2-98 93 3 0 0
1-99 125 13 0 1
2-99 739 38 0 9
1-00 2130 139 0 13
2-00 3380 191 0 42
1-01 4950 478 1 52
2-01 6250 790 5 99
1-02 6910 1351 4 135
2-02 4090 2832 5 237
1-03 3280 3769 1 280
2-03 3130 6179 3 339
1-04 2950 53652 18 853