When I do a search in google keyword tool for the phase Sliding Glass Door Window Treatments I get 5400 local monthly searches. The same phase in wordtracker receives only 33 yearly searches. I would hate to write an article around this phase only to attract about 2 potential vists a month according to wordtracker.
I am not sure, but i think WordTracker is based on actual results from not so popular search engines, so take wordtracker into context, if it gets 33 per year then thats good if other comparable keywords get like 5-10.
The google keyword tool is inherently inaccurate. Also, every keyword tool will give you different results. I may be mistaken, but doesn't wordtracker default to displaying daily searches? I'm probably wrong, but that's the impression I have.
I would recommend you these 1. Which type of match did you use when do keyword research via Google Webmaster Tools. I would recommend using "exact" match to be the most accurate. 2. If number from those 2 are still much different, stand on with number from Google. WordTracker and so on keyword tools use collected data from ISP and many way but not from Google DCs directly while Google number is show from Google database itself. It should be more accurate in this case. 3. However, even number from Google may not that accurate if those keyword is "Seasonal Keyword" type. This type of keywords will have high searches for a period of time before dropped. I assume your keyword "Sliding Glass Door Window Treatments" may have high search from some people in sometime and not a stable keyword in my opinion.