Update:

I've 'averaged' the few answers and comments and included the respective result below each question (all results are executed accordingly for some time already in most dev-tip posts). The empirical base here is obviously quite low, but so is the activity on Stack Apps in general still, hence this should do for now and can be updated/adjusted as needed.

I really like the approach code poet has taken with his dev-tip series and would like to see this evolve into a developer recipe like cookbook kinda thing/HOWTO/FAQ. However, if I look at the list of questions tagged dev-tip several questions pop up immediately. So I'd like to open a short discussion on the following early on, assuming this is a good time to refine the format without triggering to many change requirements; please consider each question as a separate topic in principle:

1. Shouldn't we drop the prefix 'Dev-Tip'?
   => YES

• I know prefixes like this are a very subjective matter of personal preference, but repeating the tag in the title seems not to be considered good practice elsewhere in the Stack Exchange network - I think it adds more noise than value, especially since all questions do start with an equally noticeable 'How to' right now ;)

2. Shouldn't we revert to the question/answer format?
   => YES

• Given the intended purpose might be getting several solutions more often than not (e.g. per language) I'd personally prefer if the questioner would state the problem/topic only in the question and add his own tip as an answer immediately.

• This would allow the question to develop more easily into the information hub for the topic at hand, e.g. link to those different implementations per language etc.

3. Should we adopt the following tags from SO?
   => see below

• language-agnostic - the question isn't related to a particular programming language but rather more a meta information regarding API usage, e.g. How to get the count of a query efficiently.
  => NO

• cross-language - the question will benefit from answers with code snippets per programming language, e.g. How to format reputation numbers similar to Stack Exchange sites.
  => MAYBE

  • I'm not entirely sure about this one, I'd appreciate the semantics outlined above but for some reason the tag has only been used 13 times on SO so far, maybe there is something better I'm not aware of right now?

4. Should we drop the 'dev-tip' tag? [added from code poets answer]
   => NO

• I agree with code poets reasoning here to keep it because this communicates the initial intent of the post being guidance, see his answer for details.

5. Should posts be community wiki immediately? [added from Kevin Montroses comment]
   => NOT JUST YET
   [nobody except Kevin seems to see this issue at the moment and he didn't provide any further reference or explanation for why he is suggesting this in particular]

• I'm aware and in favor of the community wiki concept in general and think this would make sense for the question immediately indeed. However, this would turn all answers into cwiki automatically too, which wouldn't properly honor/motivate the effort put into posting a code snippet for another programming language for example. So this is a bit difficult - I'm not into the respective meta discussions, couldn't this get sorted over time, i.e. use cwiki automatically/voluntarily for the moment and see how it evolves?

Most of this is pretty subjective and I think there is no need to argue about it other than exchanging opinions to see whether an easy agreement can be reached here or there - the dev-tip category can continue unchanged as well and will still be highly useful!