On one hand, they are cheap and easy to collect. Plus they cover a lot of figures quickly, so you don't have to wait years to get a sizable collection full of your favorite characters.
On the other hand, they're a bit too corny looking for me. The design has worked well for Diamond Select for many, many years (a design obviously inspired by the success and popularity of Medicom's Kurbick figure, which were of course inspired by LEGO's minifigures) but it's kind worn out and could use a few upgrades at this point.
Anyway-- all that aside, it looks like Star Trek will soon be rejoining the Minimates line with "Star Trek Legacy", a series that covers all the Start Trek shows and movies, all in one line, simultaneously.
In Series 1, we'll be seeing figures from Star Trek II: The Wrath of Khan, Star Trek: First Contact, Star Trek Enterprise and Star Trek Seep Space Nine.
These are set to ship in July at a price of 9.99 per set of two.