Wordtracker indroduced themselves as more of a reseach tool instead of an SEO tool which is a very clever point since SEO starts with a good foundation of selected keywords. It also has a new tool called Strategizer which makes your SEO and PPC more profitable and rewarding.

There are numerous reasons to subscribe to word tracker:

It has a trial version but other features and keywords are limited.

Note: All pricing listed at time of posting. Subject to change.