I would say, if just for the items, probably not lol. I mean, it's a bit of a time sink and besides some of the unique pets/minis the items will probably only be used for a few levels in GW2 before we find cooler gear/skins.
But, if you're looking for what is still a great game, want to know the story of what happened before GW2 & the same time get some rewards for GW2. Then yea, really worth it, great value for a low price.
There's a trial too btw, so you can see if you like it, when you buy game you can just continue with that char. No extra downloads needed, just apply key.
To be honest, if you have the time I'd really recommend playing GW before GW2. It's not needed, but it's a lot cooler when you know who Adelbern, Rurik, Gwen, etc are.
And as part of "Guild Wars Beyond", Arenanet is still adding new content to the game in the form of free mini-campaigns that kinda tie up the loose ends between GW1 & GW2:
http://wiki.guildwars.com/wiki/Beyond