I've been in the Dota 2 beta since December, and it has truly come a long way. The devs have been listening to feedback the whole way through, and they've made it a very enjoyable game. I think that people might get a bit confused with the 2 though; Dota 2 is the successor to DotA, not the sequel. It adds essentially no new content, per se, but rather quality of life fixes, and a graphical overhaul.
With regards to the actual content: IceFrog joined Valve to work on Dota 2, the successor to his game, DotA. Dota 2 is intended to remove all of the limitations of the Warcraft engine, to fix bugs that couldn't be fixed, bring the game back into 2012, and provide a base for more creative Heroes and mechanics. Currently, there's no Heroes that are intended for Dota 2, and I doubt that IceFrog will completely abandon DotA, but once the majority of the Asian gaming community transfer over to Dota 2, I imagine that IceFrog will shift his focus to Creative Director for Dota 2.
From my first impressions of the newly released cosmetics, with the exception of the silly Lederhosen Ursa, the cosmetics are all very polished, and fit the style. I think that Valve will succeed where Heroes of Newerth has failed; the skins available for Newerth change the basic silhouette of the Hero, and they broke style with some of the silly skins, making it difficult for a newcomer to recognize who is who. Let's be honest, it's not exactly hard to understand that the white and black massive thing is still Tidehunter. Anybody that gets confused by that is probably not going to perform well anyway.
The current report system is still lacking, there's still too much leniency, and trolls can often ruin several games before being put into the low priority queue, and the report system is exploitable. A team of five can all report one person, and that person could go into low priority. I think that there needs to be a reviewal system, like League of Legends' Tribunal. On release, the report system will hopefully be much more polished; currently it is only serving to keep the trolls out of the beta testing environment, and Valve will probably take it much more seriously when the people being offended are paying customers.
As for the Workshop, many of the items that have been released are community made. I think that they're all very high quality, and they, with exception of the Alpine Ursa, fit the style, and belong in the game. The submission and approval system for the Workshop is identical to the TF2 system. I would imagine that the profits from sold items would be distributed with the creator in the same way.