If you were to ask my opinion, I'd say no... he shouldn't.  Here is my logic:

1) The Leafs lack for scoring depth as things are, and Grabovski is actually one of their most polished offensive players.

2) Despite a lack of size, he is easily one of the most feisty of the Leafs forwards, and he regularly indicates a willingness to tussle with opposition defenders.  While far from intimidating, that level of push back is important to the Leafs forward corps.

3) Why rush Nazem Kadri? Let the kid play another year in junior, or let him play in the AHL, but why rush him to the NHL? He's going to have to out play NHL players to earn a roster spot out of camp. Despite what Ron Wilson is saying in the press, the long term outlook of Kadri's career, and the luxury of perspective are both things that Brian Burke needs to apply in this situation.

4) His $2.9 million a year salary is not unjustifiable, despite what other writers (here's looking at you Dave Shoalts) would have you believe. Mikhail Grabovski produced points at a rate of 0.59 ppg this past season, and 0.62 ppg the previous year. Here is a list of players around the NHL that produce points at a rate between 0.58 and 0.63 ppg over the past two years; are between the ages of 22 and 27, along with their current NHL salary cap hit:

Player (season) GP G A Pts PPG Cap Hit
Alexander Frolov (09-10) 81 19 32 51 0.63 $2.9 million
Alexandre Burrows (08-09) 82 28 23 51 0.62 $2.0 million
Mikhail Grabovski (08-09) 78 20 28 48 0.62 $850 K
Chuck Kobasew (08-09) 68 21 21 42 0.62 $2.333 million
David Backes (09-10) 79 17 31 48 0.61 $2.5 million
Patrice Bergeron (08-09) 64 8 31 39 0.61 $4.75 million
Joffrey Lupul (09-10) 23 10 4 14 0.61 $4.25 million
Andrew Ladd (08-09) 82 15 34 49 0.60 $1.55 million
Lee Stempniak (09-10) 80 28 20 48 0.60 $2.5 million
Mikhail Grabovski (09-10) 59 10 25 35 0.59 $2.9 million
Matt Moulson (09-10) 82 30 18 48 0.59 $575 K
Lee Stempniak (08-09) 75 14 30 44 0.59 $2.5 million
Brandon Yip (09-10) 32 11 8 19 0.59 $750 K
Dave Bolland (08-09) 81 19 28 47 0.58 $845,833
Steve Downie (09-10) 79 22 24 46 0.58 $821,667

On that list, Grabovski and Stempniak are the only players to appear from both years.  Players like Yip, Moulson, Downie, and Bolland were all on entry level deals at the time of their production.  Bolland has since been rewarded with a 5 year deal that pays him $3.375 million per season, but his production decreased to 16 points in 39 games or 0.41 ppg.

Stempniak's cap hit this past year was only $2.5 million, but he was paid $3.5 million, and his added goal production came in a top line role in Phoenix after the trading deadline.  Prior to the trade, he was well off his pace from the previous year.

Patrice Bergeron's production improved to 52 points in 73 games this year or 0.71 ppg, which is more in line with his salary.  Alex Burrows is performing far beyond his pay scale in Vancouver, having recorded 35 goals and 67 points in 82 games or 0.81 ppg.

Andrew Ladd has dropped back to 38 points in 82 games (0.46 ppg) this season from the highs of 2008-09, so his salary makes more sense.

In the end though, the average for that group salary wise is $2.135 million per year, and it's skewed lower by a high number of entry level deals.  The median salary for the group is $2.333 million per year, and while Grabovski's salary is well above that, his consistency of production with a wide variety of line mates leads me to the conclusion that he's capable of producing at that level regularly in the future.

If he was making $4 million a year, it would be understandable that his salary would be pointed at as a problem, but currently Grabovski is the 3rd highest paid forward on the Leafs.  It is quite possible that he will be the 4th or 5th highest paid forward when Kulemin is re-signed, and if the Leafs bring in another forward via trade.

On the team, Grabovski is the 9th highest paid player.  Does that make him the 9th most valuable player to the Leafs fortunes?  Probably not.  In fact I would argue that he's probably in the top 5 or 6 with how the team is currently constituted.

If a trade is made, and Grabovski is moved, the player(s) that come back in return need to either improve the team in the future, or make it more competitive in the short term.  Somehow I don't know what Burke could trade Grabovski for that would ensure improved play from the club in the future.  It remains to be seen, but at this point I'd say the Leafs should hold on to the crazy little guy... at least until we know Kadri is ready for the glare of the lights in Toronto.