I'm thinking of adding it.
How much is it per month and is it worth it ?

You mean the one w/ all the FSN networks? No, not worth it. Any sports on those channels is blocked out unless you are in that region. So, unless you have a desire to see the sports report for the different regions, waste of money.

The only 3 channels on the sports tier that are worth anything are ESPNU, CSTV, and Fox Soccer Channel (if you're into such things)

Only reason to add it would be if you wanted to see a lot of college sports from other regions. You also get CSTV and ESPNU.

I get it from Oct-Mar for college hockey games, and it's worth it for that purpose alone.

If you don't subscribe to any other premium channels, it's $12 a month. If you call and ask for any current "subscriber deals for the sports pack", you can get it for $2 a month for 6 months.

I've done this a couple of times, because I live in NW Ohio and don't get Fox Sports Detroit I get Fox Sports Ohio. With the Sports Pack, I get FSD and Tigers games are not blacked out. All other MLB games on other RSNs are blacked out though.

It's not worth it for most people IMO. The only reason I keep it is for TVG.

I have it for Fox Soccer Channel, OLN and Speed.

I don't get it. Why would the games be blocked out if you don't live in the same region? I thought the main reason why games get blocked out was to discourage people from just watching the game on TV, and to attend the game in person (which means bigger profits). So if I live in Boston and want to watch the game in Denver, how would that adversely affect them?

Because there is money to be made by everyone with the subscriptions to MLB Extra Innings, NFL Sunday Ticket, MLB League Pass, NHL whatever....

The owners of your local pro teams don't want you watching pro sports from other cities instead of watching your local team. If you don't live within a certain distance of a pro team (50 miles maybe?) then you probably won't have anything blacked out.

I was thinking of getting it mainly for MSG so I can watch the Rangers and Yes network for Yankee games.

I was considering this to get NESN so I could watch Red Sox games.

Again, you can't get any major league sports on these channels unless you live in the region they are broadcasting.

For example, I live in Phoenix. I can get all the Diamondbacks/Suns games on FSN when they play. If you are living in anywhere that isn't in this region, the games are blacked out.

Is that just for FSN or for all the sports channels including MSG and YES ?
So as lomg as I live in the NY area I can watch all the Ranger and Yankee games ?

Yes, but if you're in the local market you might get those anyways. I don't have the Sports Pack, but, living in South Florida, I do get Fox Sports Florida and the Sunshine Network.