Are you already using 2.5? If so, what convinced you to upgrade? What features make you glad you did?

or...

You haven't upgraded, why not? What will it take to convince you?

I use 2.49. Why haven't I upgraded? Fear. What's it going to take to convince me? I don't know, therapy? Every time I get something new I dedicate a lot of time trying to "master the beast". I'm not ready for that right now.

Well, with the release of v. 2.53, I decided I would go ahead and try it out. I have to say I like it a whole lot more than I thought I would. And reconfiguring my brain to function with the new UI was not as hard as I thought it would be. It's still too buggy and undocumented for me to switch, but I'll keep playing with it.

I've been playing with 2.54 recently. I now think I'm pretty much sold on this version. CG Cookie has a bunch of tutorials on Vimeo, so I have enough confidence to actually make stuff with it. TBH, I haven't used 24.9 since 2.54's release.

In conclusion, I think it's definitely worth the switch.

I love 2.54! Before, I used to think that Blender was only for meshing. Now that I've upgraded to 2.54, I found that Blender can do so much more. The change of layout is fantastic too; it feels so much easier to use. Blender 2.49 was just that little bit less... pretty, if you will, for me to get a grasp of what the program could actually do, if that makes sense.

So, yes. I found it was worth switching, too.

I"m using 2.55. What convinced me to upgrade, given my suspicion of beta releases? The thought that your scripts would only work with 2.5x. ^_^

Well, 2.56 has been released, and it borked my scripts. But I can tell that it's becoming more stable, because I only had to change three words to make the script work again(instead of lines of code).

eta: This is supposedly one of the last of the beta series, yay!

I'm using 2.49 and 2.56 as I'm attempting to make clothing as well as objects, so it works out pretty well. I'm still getting used the 2.5 new layout, becuase I'd gotten used to the old one over the years.

I know, I used both until I finally found where everything was. I wish I could write a script for GEOMs, but I don't know enough about the format yet.