Well, they're both legit...kinda...
The Tampa Bay Rowdies have a star above their crest for the Championship they won in the old NASL (which was the US Division 1 in the 70s and 80s) back in 1975. It's kind of hazy if they should get to wear it since it is not the same organization that won it. However, not hazy enough for it to matter to me.
The Puerto Rican Islanders' star comes from their Caribbean Football Union Championship (their version of the USOC) in 2010. Since they repeated last year, we should expect to see another star on this year's shirts. The haziness here is from the confusion on the use of stars in North America. The Cleveland City Stars added one for their USL-2 (actually Division 3)title in 2008 and Northern Kentucky University sports one for their NCAA Div. II Championship in 2010. Vancouver and Montreal have stars from their championships in the USL-1, whether the league was Canada's Div.1 league (Before Toronto joined the MLS in 2007) or not (after 2007, when MLS became Canada's Div.1 and USL-1 became their Div. 2). But, for most of the world's professional clubs, stars primarily represent a championship or championships in a FIFA Division 1 league.
Here's a wiki link to a listing of star uses on or above team crests:
http://en.wikipedia.org/wiki/Star_(football_badge)
My personal preference for professional clubs would be as follows:
1 Silver star for every 10 Division-1 league titles
1 White star for every single Division-1 league title
1 Gold star for every National Open Cup title, (or regional Open Cup, such as the CFU Championship)
1 Diamond insignia for every Confederations Champions League title.
"Open to other suggestions" invites
That little old jersey collector
Me
"Some of these players never dreamed they'd be playing at a Cup Final at Wembley - but here they are today, fulfilling those dreams" - Lawrie McMenemy, former Southampton manager
Wow. That is an extremely informative post. Your championship star indicator is a bit much for me, though.
From a design standpoint, it would just be too cluttered. Can you imagine a club with a white, silver, and gold star, plus diamonds, above their crest?
Personally, I like the notion that teams only wear a star if they win a 1st division, single table title. Other titles should be evidenced in your trophy case, not on your shirt.
But that's not really how things work here in the US, so I'm slightly torn. Maybe the diamond insignia is a good compromise. That way teams which necessarily cannot move up can still denote historic championships. (I also like this idea, because it really emphasizes the importance of the USOC.)
In any case, I hope we wear a scudetto this season.