Today's announcement by former Florida state House Speaker Marco Rubio that he will challenge Gov. Charlie Crist in a Republican primary for the state's open Senate seat in 2010 -- if, as expected, Crist jumps into the race -- sets up the latest in a series of terrific primaries on tap for next year.

Not only are there great intraparty squabbles already set in Senate races in Florida, Connecticut, Kansas, Missouri, Ohio and Texas but there are also a few potentially marquee contests on the horizon including in Pennsylvania where Sen. Arlen Specter (D) could face a challenge from Rep. Joe Sestak and/or former National Constitution Center head Joe Torsella while former Rep. Pat Toomey and former Gov. Tom Ridge might square off on the Republican side.

At the gubernatorial level, there are scads of great primaries ranging from the battle between Texas Gov. Rick Perry (R) and Sen. Kay Bailey Hutchison to the likely scrap between New York Gov. David Paterson (D) and state Attorney General Andrew Cuomo.

The Fix has made clear our feelings about primaries: we love them!

But, for today's Wag the Blog question we want your opinion on whether primaries are generally a good thing or a bad thing for the two parties.

Evidence can be cited on both sides of the argument.

It's hard to question that the prolonged battle between then Sens. Barack Obama and Hillary Rodham Clinton strengthened Democrats' hands -- from a media, messaging and voter registration perspective -- for last fall's campaign.

But, it's equally difficult to argue that Sen. Ted Kennedy's (Mass.) challenge to then President Jimmy Carter in 1980 didn't significantly weaken Carter for the general election race against Ronald Reagan.

Which side of the argument do you buy into? Do primaries -- in the main -- allow the best candidate with the most compelling message to rise to the top? Or are they typically bloody and expensive contests that distract from the general elections where there are real differences between the candidates?

Offer your thoughts in the comments section below. As always, the most insightful comments will be featured later this week in their own post.