Now we have a new lead, and a couple of engineers going to join that team full time. First of all, this is great news. I have a lot of respect for the engineer who's taking on the lead position. Having the core of team come from internal sources means the ramp-up time should be a lot shorter and less painful. So...
What's the best thing I can do to help this team be successful? I already know the worst thing I can do: pile on and drown the new guy (oops!). But how do I (and my team) do the most helpful thing?
Short answer: the best thing I can do right now is back off.
Longer answer: This team lead, and really his whole team, is in a precarious position. They have new responsibilities, a code base that could use some maintenance, a team to gel, hiring to do, etc. Oh, and everyone wants a piece of them.
Product management wants to talk about the backlog of work that hasn't been important enough before but now that we have a dedicated team we should really look at.
HR needs to help get hiring up to speed and start the flow of resumes.
The other dev leads need to take some time to transition off the old work.
QA? QA can wait. Sure, there's a lot we need - like to talk about the structural improvements we'd like to see to close out some of the testability or the holes that tend to cause a lot of different bugs. But this team isn't going to make structural changes in the next week or so. Therefore, QA can wait. The bugs are still there, the testing is still there, but waiting another week won't kill anyone.
The moral of the story is that no matter how tempting, resist the urge to join the pile jumping on top of the new team. Sit back, be glad they're working on it, and let them find their feet before you get too involved.